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Herramienta donde tendréis que desarrollar una presentación de diapositivas que ilustre el proceso seguido para desarrollar las tareas del supuesto práctico.

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Software de virtualización para crear la máquina virtual (Hipervisor Tipo II).

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VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 3. See " About VirtualBox" for an introduction.

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VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 3.

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Imagen ISO de Ubuntu Server.

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Get Ubuntu Server one of three ways; by using Multipass on your desktop, using MAAS to provision machines in your data centre or installing it directly on a server.

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Descripción de los parámetros del fichero de configuración /etc/vsftpd.conf

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Index Return to Main Contents
NAME
vsftpd.conf - config file for vsftpd
DESCRIPTION
vsftpd.conf may be used to control various aspects of vsftpd's behaviour. By default, vsftpd looks for this file at the location /etc/vsftpd.conf. However, you may override this by specifying a command line argument to vsftpd. The command line argument is the pathname of the configuration file for vsftpd. This behaviour is useful because you may wish to use an advanced inetd such asxinetd to launch vsftpd with different configuration files on a per virtual host basis.
FORMAT
The format of vsftpd.conf is very simple. Each line is either a comment or a directive. Comment lines start with a # and are ignored. A directive line has the format:
option=value

It is important to note that it is an error to put any space between the option, = and value.

Each setting has a compiled in default which may be modified in the configuration file.

BOOLEAN OPTIONS
Below is a list of boolean options. The value for a boolean option may be set to YES orNO.

allow_anon_ssl

Only applies if ssl_enable is active. If set to YES, anonymous users will be allowed to use secured SSL connections.
Default: NO

anon_mkdir_write_enable

If set to YES, anonymous users will be permitted to create new directories under certain conditions. For this to work, the option write_enable must be activated, and the anonymous ftp user must have write permission on the parent directory.
Default: NO

anon_other_write_enable

If set to YES, anonymous users will be permitted to perform write operations other than upload and create directory, such as deletion and renaming. This is generally not recommended but included for completeness.
Default: NO

anon_upload_enable

If set to YES, anonymous users will be permitted to upload files under certain conditions. For this to work, the option write_enable must be activated, and the anonymous ftp user must have write permission on desired upload locations. This setting is also required for virtual users to upload; by default, virtual users are treated with anonymous (i.e. maximally restricted) privilege.
Default: NO

anon_world_readable_only

When enabled, anonymous users will only be allowed to download files which are world readable. This is recognising that the ftp user may own files, especially in the presence of uploads.
Default: YES

anonymous_enable

Controls whether anonymous logins are permitted or not. If enabled, both the usernames ftp andanonymous are recognised as anonymous logins.
Default: YES

ascii_download_enable

When enabled, ASCII mode data transfers will be honoured on downloads.
Default: NO

ascii_upload_enable

When enabled, ASCII mode data transfers will be honoured on uploads.
Default: NO

async_abor_enable

When enabled, a special FTP command known as "async ABOR" will be enabled. Only ill advised FTP clients will use this feature. Additionally, this feature is awkward to handle, so it is disabled by default. Unfortunately, some FTP clients will hang when cancelling a transfer unless this feature is available, so you may wish to enable it.
Default: NO

background

When enabled, and vsftpd is started in "listen" mode, vsftpd will background the listener process. i.e. control will immediately be returned to the shell which launched vsftpd.
Default: NO

check_shell

Note! This option only has an effect for non-PAM builds of vsftpd. If disabled, vsftpd will not check /etc/shells for a valid user shell for local logins.
Default: YES

chmod_enable

When enabled, allows use of the SITE CHMOD command. NOTE! This only applies to local users. Anonymous users never get to use SITE CHMOD.
Default: YES

chown_uploads

If enabled, all anonymously uploaded files will have the ownership changed to the user specified in the setting chown_username. This is useful from an administrative, and perhaps security, standpoint.
Default: NO

chroot_list_enable

If activated, you may provide a list of local users who are placed in a chroot() jail in their home directory upon login. The meaning is slightly different if chroot_local_user is set to YES. In this case, the list becomes a list of users which are NOT to be placed in a chroot() jail. By default, the file containing this list is /etc/vsftpd.chroot_list, but you may override this with the chroot_list_file setting.
Default: NO

chroot_local_user

If set to YES, local users will be (by default) placed in a chroot() jail in their home directory after login. Warning: This option has security implications, especially if the users have upload permission, or shell access. Only enable if you know what you are doing. Note that these security implications are not vsftpd specific. They apply to all FTP daemons which offer to put local users in chroot() jails.
Default: NO

connect_from_port_20

This controls whether PORT style data connections use port 20 (ftp-data) on the server machine. For security reasons, some clients may insist that this is the case. Conversely, disabling this option enables vsftpd to run with slightly less privilege.
Default: NO (but the sample config file enables it)

debug_ssl

If true, OpenSSL connection diagnostics are dumped to the vsftpd log file. (Added in v2.0.6).
Default: NO

delete_failed_uploads

If true, any failed upload files are deleted. (Added in v2.0.7).
Default: NO

deny_email_enable

If activated, you may provide a list of anonymous password e-mail responses which cause login to be denied. By default, the file containing this list is /etc/vsftpd.banned_emails, but you may override this with the banned_email_file setting.
Default: NO

dirlist_enable

If set to NO, all directory list commands will give permission denied.
Default: YES

dirmessage_enable

If enabled, users of the FTP server can be shown messages when they first enter a new directory. By default, a directory is scanned for the file .message, but that may be overridden with the configuration setting message_file.
Default: NO (but the sample config file enables it)

download_enable

If set to NO, all download requests will give permission denied.
Default: YES

dual_log_enable

If enabled, two log files are generated in parallel, going by default to /var/log/xferlog and/var/log/vsftpd.log. The former is a wu-ftpd style transfer log, parseable by standard tools. The latter is vsftpd's own style log.
Default: NO

force_dot_files

If activated, files and directories starting with . will be shown in directory listings even if the "a" flag was not used by the client. This override excludes the "." and ".." entries.
Default: NO

force_anon_data_ssl

Only applies if ssl_enable is activated. If activated, all anonymous logins are forced to use a secure SSL connection in order to send and receive data on data connections.
Default: NO

force_anon_logins_ssl

Only applies if ssl_enable is activated. If activated, all anonymous logins are forced to use a secure SSL connection in order to send the password.
Default: NO

force_local_data_ssl

Only applies if ssl_enable is activated. If activated, all non-anonymous logins are forced to use a secure SSL connection in order to send and receive data on data connections.
Default: YES

force_local_logins_ssl

Only applies if ssl_enable is activated. If activated, all non-anonymous logins are forced to use a secure SSL connection in order to send the password.
Default: YES

guest_enable

If enabled, all non-anonymous logins are classed as "guest" logins. A guest login is remapped to the user specified in the guest_username setting.
Default: NO

hide_ids

If enabled, all user and group information in directory listings will be displayed as "ftp".
Default: NO

implicit_ssl

If enabled, an SSL handshake is the first thing expect on all connections (the FTPS protocol). To support explicit SSL and/or plain text too, a separate vsftpd listener process should be run.
Default: NO

listen

If enabled, vsftpd will run in standalone mode. This means that vsftpd must not be run from an inetd of some kind. Instead, the vsftpd executable is run once directly. vsftpd itself will then take care of listening for and handling incoming connections.
Default: YES

listen_ipv6

Like the listen parameter, except vsftpd will listen on an IPv6 socket instead of an IPv4 one. This parameter and the listen parameter are mutually exclusive.
Default: NO

local_enable

Controls whether local logins are permitted or not. If enabled, normal user accounts in /etc/passwd (or wherever your PAM config references) may be used to log in. This must be enable for any non-anonymous login to work, including virtual users.
Default: NO

lock_upload_files

When enabled, all uploads proceed with a write lock on the upload file. All downloads proceed with a shared read lock on the download file. WARNING! Before enabling this, be aware that malicious readers could starve a writer wanting to e.g. append a file.
Default: YES

log_ftp_protocol

When enabled, all FTP requests and responses are logged, providing the option xferlog_std_format is not enabled. Useful for debugging.
Default: NO

ls_recurse_enable

When enabled, this setting will allow the use of "ls -R". This is a minor security risk, because a ls -R at the top level of a large site may consume a lot of resources.
Default: NO

mdtm_write

When enabled, this setting will allow MDTM to set file modification times (subject to the usual access checks).
Default: YES

no_anon_password

When enabled, this prevents vsftpd from asking for an anonymous password - the anonymous user will log straight in.
Default: NO

no_log_lock

When enabled, this prevents vsftpd from taking a file lock when writing to log files. This option should generally not be enabled. It exists to workaround operating system bugs such as the Solaris / Veritas filesystem combination which has been observed to sometimes exhibit hangs trying to lock log files.
Default: NO

one_process_model

If you have a Linux 2.4 kernel, it is possible to use a different security model which only uses one process per connection. It is a less pure security model, but gains you performance. You really don't want to enable this unless you know what you are doing, and your site supports huge numbers of simultaneously connected users.
Default: NO

passwd_chroot_enable

If enabled, along with chroot_local_user , then a chroot() jail location may be specified on a per-user basis. Each user's jail is derived from their home directory string in /etc/passwd. The occurrence of /./ in the home directory string denotes that the jail is at that particular location in the path.
Default: NO

pasv_addr_resolve

Set to YES if you want to use a hostname (as opposed to IP address) in the pasv_address option.
Default: NO

pasv_enable

Set to NO if you want to disallow the PASV method of obtaining a data connection.
Default: YES

pasv_promiscuous

Set to YES if you want to disable the PASV security check that ensures the data connection originates from the same IP address as the control connection. Only enable if you know what you are doing! The only legitimate use for this is in some form of secure tunnelling scheme, or perhaps to facilitate FXP support.
Default: NO

port_enable

Set to NO if you want to disallow the PORT method of obtaining a data connection.
Default: YES

port_promiscuous

Set to YES if you want to disable the PORT security check that ensures that outgoing data connections can only connect to the client. Only enable if you know what you are doing!
Default: NO

require_cert

If set to yes, all SSL client connections are required to present a client certificate. The degree of validation applied to this certificate is controlled by validate_cert (Added in v2.0.6).
Default: NO

require_ssl_reuse

If set to yes, all SSL data connections are required to exhibit SSL session reuse (which proves that they know the same master secret as the control channel). Although this is a secure default, it may break many FTP clients, so you may want to disable it. For a discussion of the consequences, see http://scarybeastsecurity.blogspot.com/2009/02/vsftpd-210-released.html (Added in v2.1.0).
Default: YES

run_as_launching_user

Set to YES if you want vsftpd to run as the user which launched vsftpd. This is useful where root access is not available. MASSIVE WARNING! Do NOT enable this option unless you totally know what you are doing, as naive use of this option can create massive security problems. Specifically, vsftpd does not / cannot use chroot technology to restrict file access when this option is set (even if launched by root). A poor substitute could be to use a deny_file setting such as {/*,*..*}, but the reliability of this cannot compare to chroot, and should not be relied on. If using this option, many restrictions on other options apply. For example, options requiring privilege such as non-anonymous logins, upload ownership changing, connecting from port 20 and listen ports less than 1024 are not expected to work. Other options may be impacted.
Default: NO

secure_email_list_enable

Set to YES if you want only a specified list of e-mail passwords for anonymous logins to be accepted. This is useful as a low-hassle way of restricting access to low-security content without needing virtual users. When enabled, anonymous logins are prevented unless the password provided is listed in the file specified by the email_password_file setting. The file format is one password per line, no extra whitespace. The default filename is /etc/vsftpd.email_passwords.
Default: NO

session_support

This controls whether vsftpd attempts to maintain sessions for logins. If vsftpd is maintaining sessions, it will try and update utmp and wtmp. It will also open a pam_session if using PAM to authenticate, and only close this upon logout. You may wish to disable this if you do not need session logging, and you wish to give vsftpd more opportunity to run with less processes and / or less privilege. NOTE - utmp and wtmp support is only provided with PAM enabled builds.
Default: NO

setproctitle_enable

If enabled, vsftpd will try and show session status information in the system process listing. In other words, the reported name of the process will change to reflect what a vsftpd session is doing (idle, downloading etc). You probably want to leave this off for security purposes.
Default: NO

ssl_enable

If enabled, and vsftpd was compiled against OpenSSL, vsftpd will support secure connections via SSL. This applies to the control connection (including login) and also data connections. You'll need a client with SSL support too. NOTE!! Beware enabling this option. Only enable it if you need it. vsftpd can make no guarantees about the security of the OpenSSL libraries. By enabling this option, you are declaring that you trust the security of your installed OpenSSL library.
Default: NO

ssl_request_cert

If enabled, vsftpd will request (but not necessarily require; see require_cert)acertificateonincomingSSLconnections.Normallythis should not cause any trouble at all, but IBM zOS seems to have issues. (New in v2.0.7).
Default: YES

ssl_sslv2

Only applies if ssl_enable is activated. If enabled, this option will permit SSL v2 protocol connections. TLS v1 connections are preferred.
Default: NO

ssl_sslv3

Only applies if ssl_enable is activated. If enabled, this option will permit SSL v3 protocol connections. TLS v1 connections are preferred.
Default: NO

ssl_tlsv1

Only applies if ssl_enable is activated. If enabled, this option will permit TLS v1 protocol connections. TLS v1 connections are preferred.
Default: YES

strict_ssl_read_eof

If enabled, SSL data uploads are required to terminate via SSL, not an EOF on the socket. This option is required to be sure that an attacker did not terminate an upload prematurely with a faked TCP FIN. Unfortunately, it is not enabled by default because so few clients get it right. (New in v2.0.7).
Default: NO

strict_ssl_write_shutdown

If enabled, SSL data downloads are required to terminate via SSL, not an EOF on the socket. This is off by default as I was unable to find a single FTP client that does this. It is minor. All it affects is our ability to tell whether the client confirmed full receipt of the file. Even without this option, the client is able to check the integrity of the download. (New in v2.0.7).
Default: NO

syslog_enable

If enabled, then any log output which would have gone to /var/log/vsftpd.log goes to the system log instead. Logging is done under the FTPD facility.
Default: NO

tcp_wrappers

If enabled, and vsftpd was compiled with tcp_wrappers support, incoming connections will be fed through tcp_wrappers access control. Furthermore, there is a mechanism for per-IP based configuration. If tcp_wrappers sets the VSFTPD_LOAD_CONF environment variable, then the vsftpd session will try and load the vsftpd configuration file specified in this variable.
Default: NO

text_userdb_names

By default, numeric IDs are shown in the user and group fields of directory listings. You can get textual names by enabling this parameter. It is off by default for performance reasons.
Default: NO

tilde_user_enable

If enabled, vsftpd will try and resolve pathnames such as ~chris/pics, i.e. a tilde followed by a username. Note that vsftpd will always resolve the pathnames ~ and ~/something (in this case the ~ resolves to the initial login directory). Note that ~user paths will only resolve if the file /etc/passwd may be found within the _current_ chroot() jail.
Default: NO

use_localtime

If enabled, vsftpd will display directory listings with the time in your local time zone. The default is to display GMT. The times returned by the MDTM FTP command are also affected by this option.
Default: NO

use_sendfile

An internal setting used for testing the relative benefit of using the sendfile() system call on your platform.
Default: YES

userlist_deny

This option is examined if userlist_enable is activated. If you set this setting to NO, then users will be denied login unless they are explicitly listed in the file specified byuserlist_file. When login is denied, the denial is issued before the user is asked for a password.
Default: YES

userlist_enable

If enabled, vsftpd will load a list of usernames, from the filename given by userlist_file. If a user tries to log in using a name in this file, they will be denied before they are asked for a password. This may be useful in preventing cleartext passwords being transmitted. See alsouserlist_deny.
Default: NO

validate_cert

If set to yes, all SSL client certificates received must validate OK. Self-signed certs do not constitute OK validation. (New in v2.0.6).
Default: NO

virtual_use_local_privs

If enabled, virtual users will use the same privileges as local users. By default, virtual users will use the same privileges as anonymous users, which tends to be more restrictive (especially in terms of write access).
Default: NO

write_enable

This controls whether any FTP commands which change the filesystem are allowed or not. These commands are: STOR, DELE, RNFR, RNTO, MKD, RMD, APPE and SITE.
Default: NO

xferlog_enable

If enabled, a log file will be maintained detailling uploads and downloads. By default, this file will be placed at /var/log/vsftpd.log, but this location may be overridden using the configuration setting vsftpd_log_file.
Default: NO (but the sample config file enables it)

xferlog_std_format

If enabled, the transfer log file will be written in standard xferlog format, as used by wu-ftpd. This is useful because you can reuse existing transfer statistics generators. The default format is more readable, however. The default location for this style of log file is /var/log/xferlog, but you may change it with the setting xferlog_file.
Default: NO

NUMERIC OPTIONS
Below is a list of numeric options. A numeric option must be set to a non negative integer. Octal numbers are supported, for convenience of the umask options. To specify an octal number, use 0 as the first digit of the number.

accept_timeout

The timeout, in seconds, for a remote client to establish connection with a PASV style data connection.
Default: 60

anon_max_rate

The maximum data transfer rate permitted, in bytes per second, for anonymous clients.
Default: 0 (unlimited)

anon_umask

The value that the umask for file creation is set to for anonymous users. NOTE! If you want to specify octal values, remember the "0" prefix otherwise the value will be treated as a base 10 integer!
Default: 077

chown_upload_mode

The file mode to force for chown()ed anonymous uploads. (Added in v2.0.6).
Default: 0600

connect_timeout

The timeout, in seconds, for a remote client to respond to our PORT style data connection.
Default: 60

data_connection_timeout

The timeout, in seconds, which is roughly the maximum time we permit data transfers to stall for with no progress. If the timeout triggers, the remote client is kicked off.
Default: 300

delay_failed_login

The number of seconds to pause prior to reporting a failed login.
Default: 1

delay_successful_login

The number of seconds to pause prior to allowing a successful login.
Default: 0

file_open_mode

The permissions with which uploaded files are created. Umasks are applied on top of this value. You may wish to change to 0777 if you want uploaded files to be executable.
Default: 0666

ftp_data_port

The port from which PORT style connections originate (as long as the poorly named connect_from_port_20 is enabled).
Default: 20

idle_session_timeout

The timeout, in seconds, which is the maximum time a remote client may spend between FTP commands. If the timeout triggers, the remote client is kicked off.
Default: 300

listen_port

If vsftpd is in standalone mode, this is the port it will listen on for incoming FTP connections.
Default: 21

local_max_rate

The maximum data transfer rate permitted, in bytes per second, for local authenticated users.
Default: 0 (unlimited)

local_umask

The value that the umask for file creation is set to for local users. NOTE! If you want to specify octal values, remember the "0" prefix otherwise the value will be treated as a base 10 integer!
Default: 077

max_clients

If vsftpd is in standalone mode, this is the maximum number of clients which may be connected. Any additional clients connecting will get an error message.
Default: 0 (unlimited)

max_login_fails

After this many login failures, the session is killed.
Default: 3

max_per_ip

If vsftpd is in standalone mode, this is the maximum number of clients which may be connected from the same source internet address. A client will get an error message if they go over this limit.
Default: 0 (unlimited)

pasv_max_port

The maximum port to allocate for PASV style data connections. Can be used to specify a narrow port range to assist firewalling.
Default: 0 (use any port)

pasv_min_port

The minimum port to allocate for PASV style data connections. Can be used to specify a narrow port range to assist firewalling.
Default: 0 (use any port)

trans_chunk_size

You probably don't want to change this, but try setting it to something like 8192 for a much smoother bandwidth limiter.
Default: 0 (let vsftpd pick a sensible setting)

STRING OPTIONS
Below is a list of string options.

anon_root

This option represents a directory which vsftpd will try to change into after an anonymous login. Failure is silently ignored.
Default: (none)

banned_email_file

This option is the name of a file containing a list of anonymous e-mail passwords which are not permitted. This file is consulted if the option deny_email_enable is enabled.
Default: /etc/vsftpd.banned_emails

banner_file

This option is the name of a file containing text to display when someone connects to the server. If set, it overrides the banner string provided by the ftpd_banner option.
Default: (none)

ca_certs_file

This option is the name of a file to load Certificate Authority certs from, for the purpose of validating client certs. Regrettably, the default SSL CA cert paths are not used, because of vsftpd's use of restricted filesystem spaces (chroot). (Added in v2.0.6).
Default: (none)

chown_username

This is the name of the user who is given ownership of anonymously uploaded files. This option is only relevant if another option, chown_uploads, is set.
Default: root

chroot_list_file

The option is the name of a file containing a list of local users which will be placed in a chroot() jail in their home directory. This option is only relevant if the option chroot_list_enable is enabled. If the optionchroot_local_user is enabled, then the list file becomes a list of users to NOT place in a chroot() jail.
Default: /etc/vsftpd.chroot_list

cmds_allowed

This options specifies a comma separated list of allowed FTP commands (post login. USER, PASS and QUIT and others are always allowed pre-login). Other commands are rejected. This is a powerful method of really locking down an FTP server. Example: cmds_allowed=PASV,RETR,QUIT
Default: (none)

cmds_denied

This options specifies a comma separated list of denied FTP commands (post login. USER, PASS, QUIT and others are always allowed pre-login). If a command appears on both this and cmds_allowed then the denial takes precedence. (Added in v2.1.0).
Default: (none)

deny_file

This option can be used to set a pattern for filenames (and directory names etc.) which should not be accessible in any way. The affected items are not hidden, but any attempt to do anything to them (download, change into directory, affect something within directory etc.) will be denied. This option is very simple, and should not be used for serious access control - the filesystem's permissions should be used in preference. However, this option may be useful in certain virtual user setups. In particular aware that if a filename is accessible by a variety of names (perhaps due to symbolic links or hard links), then care must be taken to deny access to all the names. Access will be denied to items if their name contains the string given by hide_file, or if they match the regular expression specified by hide_file. Note that vsftpd's regular expression matching code is a simple implementation which is a subset of full regular expression functionality. Because of this, you will need to carefully and exhaustively test any application of this option. And you are recommended to use filesystem permissions for any important security policies due to their greater reliability. Supported regex syntax is any number of *, ? and unnested {,} operators. Regex matching is only supported on the last component of a path, e.g. a/b/? is supported but a/?/c is not. Example: deny_file={*.mp3,*.mov,.private}
Default: (none)

dsa_cert_file

This option specifies the location of the DSA certificate to use for SSL encrypted connections.
Default: (none - an RSA certificate suffices)

dsa_private_key_file

This option specifies the location of the DSA private key to use for SSL encrypted connections. If this option is not set, the private key is expected to be in the same file as the certificate.
Default: (none)

email_password_file

This option can be used to provide an alternate file for usage by the secure_email_list_enable setting.
Default: /etc/vsftpd.email_passwords

ftp_username

This is the name of the user we use for handling anonymous FTP. The home directory of this user is the root of the anonymous FTP area.
Default: ftp

ftpd_banner

This string option allows you to override the greeting banner displayed by vsftpd when a connection first comes in.
Default: (none - default vsftpd banner is displayed)

guest_username

See the boolean setting guest_enable for a description of what constitutes a guest login. This setting is the real username which guest users are mapped to.
Default: ftp

hide_file

This option can be used to set a pattern for filenames (and directory names etc.) which should be hidden from directory listings. Despite being hidden, the files / directories etc. are fully accessible to clients who know what names to actually use. Items will be hidden if their names contain the string given by hide_file, or if they match the regular expression specified by hide_file. Note that vsftpd's regular expression matching code is a simple implementation which is a subset of full regular expression functionality. See deny_file for details of exactly what regex syntax is supported. Example: hide_file={*.mp3,.hidden,hide*,h?}
Default: (none)

listen_address

If vsftpd is in standalone mode, the default listen address (of all local interfaces) may be overridden by this setting. Provide a numeric IP address.
Default: (none)

listen_address6

Like listen_address, but specifies a default listen address for the IPv6 listener (which is used if listen_ipv6 is set). Format is standard IPv6 address format.
Default: (none)

local_root

This option represents a directory which vsftpd will try to change into after a local (i.e. non-anonymous) login. Failure is silently ignored.
Default: (none)

message_file

This option is the name of the file we look for when a new directory is entered. The contents are displayed to the remote user. This option is only relevant if the option dirmessage_enable is enabled.
Default: .message

nopriv_user

This is the name of the user that is used by vsftpd when it wants to be totally unprivileged. Note that this should be a dedicated user, rather than nobody. The user nobody tends to be used for rather a lot of important things on most machines.
Default: nobody

pam_service_name

This string is the name of the PAM service vsftpd will use.
Default: ftp

pasv_address

Use this option to override the IP address that vsftpd will advertise in response to the PASV command. Provide a numeric IP address, unless pasv_addr_resolve is enabled, in which case you can provide a hostname which will be DNS resolved for you at startup.
Default: (none - the address is taken from the incoming connected socket)

rsa_cert_file

This option specifies the location of the RSA certificate to use for SSL encrypted connections.
Default: /usr/share/ssl/certs/vsftpd.pem

rsa_private_key_file

This option specifies the location of the RSA private key to use for SSL encrypted connections. If this option is not set, the private key is expected to be in the same file as the certificate.
Default: (none)

secure_chroot_dir

This option should be the name of a directory which is empty. Also, the directory should not be writable by the ftp user. This directory is used as a secure chroot() jail at times vsftpd does not require filesystem access.
Default: /usr/share/empty

ssl_ciphers

This option can be used to select which SSL ciphers vsftpd will allow for encrypted SSL connections. See the ciphers man page for further details. Note that restricting ciphers can be a useful security precaution as it prevents malicious remote parties forcing a cipher which they have found problems with.
Default: DES-CBC3-SHA

user_config_dir

This powerful option allows the override of any config option specified in the manual page, on a per-user basis. Usage is simple, and is best illustrated with an example. If you set user_config_dir to be/etc/vsftpd_user_conf and then log on as the user "chris", then vsftpd will apply the settings in the file/etc/vsftpd_user_conf/chris for the duration of the session. The format of this file is as detailed in this manual page! PLEASE NOTE that not all settings are effective on a per-user basis. For example, many settings only prior to the user's session being started. Examples of settings which will not affect any behviour on a per-user basis include listen_address, banner_file, max_per_ip, max_clients, xferlog_file, etc.
Default: (none)

user_sub_token

This option is useful is conjunction with virtual users. It is used to automatically generate a home directory for each virtual user, based on a template. For example, if the home directory of the real user specified via guest_username is/home/virtual/$USER, anduser_sub_token is set to$USER, then when virtual user fred logs in, he will end up (usually chroot()'ed) in the directory/home/virtual/fred. This option also takes affect iflocal_root containsuser_sub_token.
Default: (none)

userlist_file

This option is the name of the file loaded when the userlist_enable option is active.
Default: /etc/vsftpd.user_list

vsftpd_log_file

This option is the name of the file to which we write the vsftpd style log file. This log is only written if the option xferlog_enable is set, andxferlog_std_format is NOT set. Alternatively, it is written if you have set the optiondual_log_enable. One further complication - if you have setsyslog_enable, then this file is not written and output is sent to the system log instead.
Default: /var/log/vsftpd.log

xferlog_file

This option is the name of the file to which we write the wu-ftpd style transfer log. The transfer log is only written if the option xferlog_enable is set, along withxferlog_std_format. Alternatively, it is written if you have set the optiondual_log_enable.
Default: /var/log/xferlog

AUTHOR
scarybeasts@gmail.com
Index
This document was created by man2html, using the manual pages.
Time: 01:07:21 GMT, May 28, 2009

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Index Return to Main Contents vsftpd.conf - config file for vsftpd vsftpd.conf may be used to control various aspects of vsftpd's behaviour. By default, vsftpd looks for this file at the location /etc/vsftpd.conf. However, you may override this by specifying a command line argument to vsftpd.

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Video de ayuda para instalar el servicio VSFTPD.

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Instalación de FTP en Ubuntu Server 20.04

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Vídeo de ayuda para configurar el acceso para usuarios anónimos en VSFTPD.

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Guía para configurar el modo pasivo en el servicio VSFTPD

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Guía para configurar el modo pasivo en el servicio VSFTPD

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Esta guía os puede servir de referencia si tenéis dudas sobre cómo habilitar correctamente el modo activo del servicio VSFTPD.

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En el Modo pasivo de FTP, es el cliente quien establece la conexión al servidor a través del puerto TCP 21 y una vez establecida la conexión, el servidor abre un puerto aleatorio, por encima del 1024, al que se conectará posteriormente.

El Vsftpd permite permite activar el modo pasivo y establecer un rango de puertos aleatorios a ser usados con dicho modo.

Primero configuraremos en el fichero /etc/vsftpd/vsftpd.conf

#Bloque para el pasivo
pasv_enable=YES
pasv_min_port=10000
pasv_max_port=10100
pasv_addr_resolve=NO
pasv_address=X.X.X.X

La IP pasiva debe se la IP pública si se está usando un servidor con NAT en CentOS 6 (en algún caso he comprobado que hay que comentar esta línea, centOS 5).

Abrimos en este ejemplo el rango de puertos entre el 10000 y el 10100 (100 puertos). Ahora, lo que tenemos que hacer es aceptar ese rango en iptables para conexiones ya establecidas y relacionadas:

#FTP ACTIVO
$ iptables -I INPUT -p tcp --dport 21 -j ACCEPT
$ iptables -I INPUT -m state --state RELATED,ESTABLISHED -p tcp --dport 20 -j ACCEPT
#FTP PASIVO
$ iptables -I INPUT -m state --state ESTABLISHED,RELATED,NEW -p tcp --dport 10000:10100 -j ACCEPT

Además necesitamos cargar dos módulos de IPTABLES que sirven para seguir las conexiones FTP y llevar control sobre éstas. Son nf_conntrack_ftp e nf_nat_ftp, El primer es necesario siempre y el segundo se puede obviar si no se trabaja con NAT.

Se deben incluir en /etc/sysconf/iptables-config:

IPTABLES_MODULES="nf_conntrack_ftp nf_nat_ftp"

Comprobar si el módulo está cargado con:

$ lsmod | grep ip

Por supuesto, si el servidor está detrás de un firewall, éste deberá abrir los puertos comentados anteriormente.

AÑADIDO (25/3/2015):

Si tienes un kernel 2.6.19 or anterior, reeplaza nf_conntrack_ftp por ip_conntrack_ftp. Similarmente, reemplaza nf_nat_ftp por ip_nat_ftp.

$modprobe ip_conntrack_ftp
$modprobe ip_nat_ftp

Si queremos que sea persistente:

cd /etc/sysconfig/modules

Crear un fichero, por ejemplo ftp.modules

$cat ftp.modules

#!/bin/sh
MODULES="ip_conntrack_ftp ip_nat_ftp"
for i in $MODULES ; do
        modprobe $i >/dev/null 2>&1
done

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En el Modo pasivo de FTP, es el cliente quien establece la conexión al servidor a través del puerto TCP 21 y una vez establecida la conexión, el servidor abre un puerto aleatorio, por encima del 1024, al que se conectará posteriormente.

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Si todavía tenéis dudas sobre las diferencias entre los dos modos de funcionamiento de un servidor FTP os recomiendo que reviséis este artículo.

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El FTP (Protocolo de transferencia de archivos) es un servicio basado en TCP (Protocolo de control de transmisión), ampliamente utilizado para transferir archivos a través de redes de datos.

El término FTP puede referirse tanto al protocolo, como al programa que implementa este protocolo (Servidor FTP, Cliente FTP). Este, utiliza dos modos de operación, activo y pasivo. Conozcamos entonces qué los diferencia.

Los dos modos FTP funcionan según la configuración del servidor y del cliente. Ambos utilizan dos canales de comunicación entre el servidor, el de comandos y el de datos, separados por dos conexiones TCP. El canal de comandos se utiliza, como su nombre indica, para enviar comandos y recibir la respuesta. El canal de datos se utiliza para transferir datos.

1. FTP Modo activo (predeterminado)

Este modo funciona cuando el cliente solicita el servidor, enviando un comando PORT, a través de un puerto aleatorio, con un paquete dirigido al puerto 21, a fin de transferir un archivo. Una vez establecida la conexión, el servidor inicia otra.

El servidor, a través del puerto 20, se pone en contacto inmediatamente con el puerto siguiente del cliente, es decir, imaginemos que el puerto utilizado en la primera conexión, por este, fue el 1500, la utilizada a efectos de la segunda conexión será la 1501, canal de datos.

Una vez establecida la conexión, todas las transferencias de archivos se realizan a través de los mismos puertos entre el cliente y el servidor. Por lo tanto, el cliente establece el canal de comandos, pero es el servidor que establece el canal de datos.

En el segundo esquema, la presencia de un firewall bloquea el intento de comunicación entre servidor y cliente, ya que el servidor utiliza un puerto diferente de la primera conexión.

2. FTP Modo Pasivo

En este, el cliente también se pone en contacto con el puerto 21 del servidor FTP a través de un comando PASV. En lugar de iniciar una segunda conexión de inmediato, el servidor responde que el cliente sólo puede ponerse en contacto con un segundo puerto diferente a la primera. Se realiza una segunda conexión entre el cliente y el servidor para la transferencia de datos.

El firewall no bloquea el intento de comunicación entre el servidor y el cliente, ya que ha sido el cliente quien inició la conexión ambas veces.

El modo pasivo se utiliza generalmente en situaciones que el servidor FTP no puede establecer el canal de datos, por culpa del firewall, aunque exista una regla en el servidor FTP.

Para un mejor control sobre la red, lo más indicado será utilizar el modo activo, que sólo requiere la apertura de los puertos 20 y 21. Ya que el modo pasivo, obliga la apertura de varios puertos, dejando la red más expuesta y con varios puntos de vulnerabilidad, precisamente por estar más puertos accesibles.

3. Conclusión

Estas son las principales diferencias entre los modos Activo y Pasivo del protocolo FTP. Es importante conocerlas para poder adaptarse en situaciones en que estemos con problemas o que tengamos que adaptarnos a una red con un firewall más restrictivo.
Resumiendo (Modo activo):

El cliente abre el canal de comandos a través del puerto 1500.

Envía el comando PORT para el puerto 21 del servidor.

El servidor confirma la conexión del canal de comandos.

Abre el canal de datos en el puerto 20 para el cliente en el puerto 1501.

El cliente confirma la conexión por el canal de datos.

Los canales de comandos y datos están abiertos y listos para su actividad.

Resumiendo (Modo Pasivo):

El cliente abre el canal de comandos a través del puerto 1500.

Envía el comando PASV al servidor dirigido al puerto 21.

El comando cambia la transmisión al modo pasivo.

A través del canal de comandos, el servidor envía al cliente el puerto que escuchará el canal de datos, por ejemplo 2345.

El cliente abre el canal de datos en el puerto 1501 para el puerto 2345 del servidor.

El servidor confirma la conexión del canal de datos.

Los canales de comandos y datos están abiertos y listos para su actividad.

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Esta son las diferencias entre el Modo FTP Activo y Pasivo - CCNA

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El término FTP puede referirse tanto al protocolo, como al programa que implementa este protocolo (Servidor FTP, Cliente FTP). Utiliza dos modos de operación, activo y pasivo ➨ Aquí las diferencias.

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Ejemplos de los parámetros modificados para establecer distintas configuraciones en VSFTPD

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Toda la configuración de vsftpd es manejada por su archivo de configuración, /etc/vsftpd/vsftpd.conf. Cada directriz está en su propia línea dentro del archivo y sigue el formato siguiente: = Se debe colocar el símbolo de almohadilla (#) antes de una línea en comentarios. El demonio ignorará cualquier línea en comentarios.

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Guía de configuración del modo de transferencia con distintos clientes gráficos FTP

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Guía de configuración del modo de transferencia con distintos clientes gráficos FTP

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En este artículo encontraréis la forma de cambiar fácilmente el modo de transferencia que queráis utilizar para realizar una transferencia entre el cliente y servidor FTP.

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1. Instalación de vsftpd (servidor FTP) en Ubuntu Server

Tarea a realizar: Instalación de vsftpd (servidor FTP) en Ubuntu Server Organización temporal: 1 hora de clase. Agrupamiento: Parejas Herramienta digital: Google Presentaciones Aclaraciones: Debéis añadir las capturas de pantalla del proceso seguido para resolver la tarea en una presentación de diapositivas mediante Google Presentaciones. Es obligatorio añadir una marca de agua a cada captura de pantalla con vuestros nombres, para ello podéis utilizar la siguiente herramienta online (https://www.iloveimg.com/es/marca-de-agua). Posteriormente, una vez finalizada las tareas asociadas a este supuesto práctico, tendréis que realizar una exposición donde expliquéis el proceso seguido apoyándoos de la presentación de diapositivas que desarrolléis.

2. Conexión al servidor FTP en modo anónimo

Tarea a realizar: Conexión al servidor FTP en modo anónimo Organización temporal: 1 hora de clase. Agrupamiento: Parejas Herramienta digital: Google Presentaciones Aclaraciones: Debéis añadir las capturas de pantalla del proceso seguido para resolver la tarea en una presentación de diapositivas mediante Google Presentaciones. Es obligatorio añadir una marca de agua a cada captura de pantalla con vuestros nombres, para ello podéis utilizar la siguiente herramienta online (https://www.iloveimg.com/es/marca-de-agua). Posteriormente, una vez finalizada las tareas asociadas a este supuesto práctico, tendréis que realizar una exposición donde expliquéis el proceso seguido apoyándoos de la presentación de diapositivas que desarrolléis.

3. Configuración del servidor FTP en modo activo

Tarea a realizar: Configuración del servidor FTP en modo activo Organización temporal: 1 hora de clase. Agrupamiento: Parejas Herramienta digital: Google Presentaciones Aclaraciones: Debéis añadir las capturas de pantalla del proceso seguido para resolver la tarea en una presentación de diapositivas mediante Google Presentaciones. Es obligatorio añadir una marca de agua a cada captura de pantalla con vuestros nombres, para ello podéis utilizar la siguiente herramienta online (https://www.iloveimg.com/es/marca-de-agua). Posteriormente, una vez finalizada las tareas asociadas a este supuesto práctico, tendréis que realizar una exposición donde expliquéis el proceso seguido apoyándoos de la presentación de diapositivas que desarrolléis.

4. Configuración del servidor FTP en modo pasivo

Tarea a realizar: Configuración del servidor FTP en modo pasivo Organización temporal: 1 hora de clase. Agrupamiento: Parejas Herramienta digital: Google Presentaciones Aclaraciones: Debéis añadir las capturas de pantalla del proceso seguido para resolver la tarea en una presentación de diapositivas mediante Google Presentaciones. Es obligatorio añadir una marca de agua a cada captura de pantalla con vuestros nombres, para ello podéis utilizar la siguiente herramienta online (https://www.iloveimg.com/es/marca-de-agua). Posteriormente, una vez finalizada las tareas asociadas a este supuesto práctico, tendréis que realizar una exposición donde expliquéis el proceso seguido apoyándoos de la presentación de diapositivas que desarrolléis.

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Tarea a realizar: Instalación de vsftpd (servidor FTP) en Ubuntu Server Organización temporal: 1 hora de clase. Agrupamiento: Parejas Herramienta digital: Google Presentaciones Aclaraciones: Debéis añadir las capturas de pantalla del proceso seguido para resolver la tarea en una presentación de diapositivas mediante Google Presentaciones.

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Página de descarga del cliente FTP FileZilla para Windows x64.

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The latest stable version of FileZilla Client is 3.65.0

Please select the file appropriate for your platform below.

Windows (64bit x86)

This installer may include bundled offers. Check below for more options.

The 64bit versions of Windows 8.1, 10 and 11 are supported.

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Download FileZilla Client for Windows (64bit x86)

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Download FileZilla Client 3.65.0 for Windows (64bit x86)