# wildcard-file() source options The `wildcard-file()` driver has the following options: ## base-dir() | ---|--- Type: | path without filename Default: | _Description:_ The path to the directory that contains the log files to monitor, for example, `base-dir("/var/log")`. To monitor also the subdirectories of the base directory, use the `recursive(yes)` option. For details, see [recursive()](../../../docs/axosyslog-core/chapter-sources/configuring-sources-wildcard-file/reference-source-wildcard-file/index.md#source-wildcard-file-recursive). Warning If you use multiple `wildcard-file()` sources in your configuration, make sure that the files and folders that match the wildcards do not overlap. That is, every file and folder should belong to only one file source. Monitoring a file from multiple wildcard sources can lead to data loss. ``` source s_files { wildcard-file( base-dir("/var/log") filename-pattern("*.log") recursive(no) follow-freq(1) ); }; ``` ## check-hostname() | ---|--- Type: | boolean (`yes` or `no`) Default: | Use the global `check-hostname()` option, which defaults to `no`. _Description:_ When receiving messages, AxoSyslog can check whether the hostname contains valid characters. Valid characters are: * alphanumeric characters (A-Z, a-z, 0-9) * the dash (`-`) and underscore (`_`) characters * the dot (`.`) and the colon (`:`) characters * the `@` and slash (`/`) If the hostname contains invalid characters, AxoSyslog sets the `syslog.invalid_hostname` tag for the message, and doesn’t parse the `${HOST}` field from the message. Uses the value of the [global option](../../../docs/axosyslog-core/chapter-global-options/reference-options/index.md#global-option-check-hostname) if not specified. ## default-facility() | ---|--- Type: | facility string Default: | kern _Description:_ This parameter assigns a facility value to the messages received from the file source if the message does not specify one. ## default-priority() | ---|--- Type: | priority string Default: | _Description:_ This parameter assigns an emergency level to the messages received from the file source if the message does not specify one. For example, `default-priority(warning)`. ## encoding() | ---|--- Type: | string Default: | _Description:_ Specifies the character set (encoding, for example, `UTF-8`) of messages using the legacy BSD-syslog protocol. To list the available character sets on a host, execute the `iconv -l` command. For details on how encoding affects the size of the message, see [Message size and encoding](../../../docs/axosyslog-core/chapter-concepts/concepts-message-representation/index.md). ## exclude-pattern() | ---|--- Type: | filename without path Default: | Available in AxoSyslog version 4.15 and later. _Description:_ Can be used together with `filename-pattern()` to exclude some matching files. For example: ``` wildcard-file( base-dir("") file-pattern("*.log"); exclude-pattern("*.?.log"); ); ``` ## filename-pattern() | ---|--- Type: | filename without path Default: | _Description:_ The filename to read messages from, without the path. You can use the `*` and `?` wildcard characters, without regular expression and character range support. You cannot use the `*` and `?` literally in the pattern. For example, `filename-pattern("*.log")` matches the `syslog.log` and `auth.log` files, but does not match the `access_log` file. The `filename-pattern("*log")` pattern matches all three. * `*` matches an arbitrary string, including an empty string * `?` matches an arbitrary character Warning If you use multiple `wildcard-file()` sources in your configuration, make sure that the files and folders that match the wildcards do not overlap. That is, every file and folder should belong to only one file source. Monitoring a file from multiple wildcard sources can lead to data loss. ``` source s_files { wildcard-file( base-dir("/var/log") filename-pattern("*.log") recursive(no) follow-freq(1) ); }; ``` ## flags() | ---|--- Type: | `assume-utf8`, `check-hostname`, `check-program`, `dont-store-legacy-msghdr`, `empty-lines`, `expect-hostname`, `kernel`, `no-hostname`, `no-multi-line`, `no-parse`, `sanitize-utf8`, `store-legacy-msghdr`, `store-raw-message`, `syslog-protocol`, `validate-utf8` Default: | empty set _Description:_ Specifies the log parsing options of the source. For example: ``` source { network(flags(check-hostname, check-program)); }; ``` ### assume-utf8 The `assume-utf8` flag assumes that the incoming messages are UTF-8 encoded, but does not verify the encoding. If you explicitly want to validate the UTF-8 encoding of the incoming message, use the `validate-utf8` flag. ### check-hostname When receiving messages, AxoSyslog can check whether the hostname contains valid characters. Valid characters are: * alphanumeric characters (A-Z, a-z, 0-9) * the dash (`-`) and underscore (`_`) characters * the dot (`.`) and the colon (`:`) characters * the `@` and slash (`/`) If the hostname contains invalid characters, AxoSyslog sets the `syslog.invalid_hostname` tag for the message, and doesn’t parse the `${HOST}` field from the message. ### check-program Available in version 4.10 and later. If the `check-program` flag is enabled, AxoSyslog validates the `${PROGRAM}` field for RFC3164-formatted messages. Valid program names meet the following criteria: * Contain only these characters: `[a-zA-Z0-9-_/().]` * Include at least one alphabetical character. If the program name fails validation, it is considered to be part of the log message. ### dont-store-legacy-msghdr By default, AxoSyslog stores the original incoming header of the log message. This is useful if the original format of a non-syslog-compliant message must be retained (AxoSyslog automatically corrects minor header errors, for example, adds a whitespace before `msg` in the following message: `Jan 22 10:06:11 host program:msg`). If you do not want to store the original header of the message, enable the `dont-store-legacy-msghdr` flag. ### empty-lines Use the `empty-lines` flag to keep the empty lines of the messages. By default, AxoSyslog removes empty lines automatically. ### exit-on-eof If this flag is set on a source, AxoSyslog stops when an EOF (end of file) is received. Available in version 4.9 and later. ### expect-hostname If the `expect-hostname` flag is enabled, AxoSyslog will assume that the log message contains a hostname and parse the message accordingly. This is the default behavior for TCP sources. Note that pipe sources use the `no-hostname` flag by default. ### guess-timezone Attempt to guess the timezone of the message if this information is not available in the message. Works when the incoming message stream is close to real time, and the timezone information is missing from the timestamp. ### kernel The `kernel` flag makes the source default to the `LOG_KERN | LOG_NOTICE` priority if not specified otherwise. ### no-header The `no-header` flag triggers AxoSyslog to parse only the `PRI` field of incoming messages, and put the rest of the message contents into `$MSG`. Its functionality is similar to that of the `no-parse` flag, except the `no-header` flag does not skip the `PRI` field. Note Essentially, the `no-header` flag signals AxoSyslog that the `syslog` header is not present (or does not adhere to the conventions / RFCs), so the entire message (except from the `PRI` field) is put into `$MSG`. The following example illustrates using the `no-header` flag with the `syslog-parser()` parser: ``` parser p_syslog { syslog-parser( flags(no-header) ); }; ``` ### no-hostname Enable the `no-hostname` flag if the log message does not include the hostname of the sender host. That way AxoSyslog assumes that the first part of the message header is ${PROGRAM} instead of ${HOST}. For example: ``` source s_dell { network( port(2000) flags(no-hostname) ); }; ``` ### no-multi-line The `no-multi-line` flag disables line-breaking in the messages: the entire message is converted to a single line. Note that this happens only if the underlying transport method actually supports multi-line messages. Currently the `file()` and `pipe()` drivers support multi-line messages. ### no-parse By default, AxoSyslog parses incoming messages as syslog messages. The `no-parse` flag completely disables syslog message parsing and processes the complete line as the message part of a syslog message. The AxoSyslog application will generate a new syslog header (timestamp, host, and so on) automatically and put the entire incoming message into the MESSAGE part of the syslog message (available using the `${MESSAGE}` macro). This flag is useful for parsing messages not complying to the syslog format. If you are using the `flags(no-parse)` option, then syslog message parsing is completely disabled, and the entire incoming message is treated as the ${MESSAGE} part of a syslog message. In this case, AxoSyslog generates a new syslog header (timestamp, host, and so on) automatically. Note that even though `flags(no-parse)` disables message parsing, some flags can still be used, for example, the `no-multi-line` flag. ### sanitize-utf8 When using the `sanitize-utf8` flag, AxoSyslog converts non-UTF-8 input to an escaped form, which is valid UTF-8. Prior to version 4.6, this flag worked only when parsing RFC3164 messages. Starting with version 4.6, it works also for RFC5424 and raw messages. ### store-legacy-msghdr By default, AxoSyslog stores the original incoming header of the log message, so this flag is active. To disable it, use the `dont-store-legacy-msghdr` flag. ### store-raw-message Save the original message as received from the client in the `${RAWMSG}` macro. You can forward this raw message in its original form to another AxoSyslog node using the [`syslog-ng()` destination](../../../docs/axosyslog-core/chapter-destinations/destination-syslog-ng/index.md), or to a SIEM system, ensuring that the SIEM can process it. Available only in 3.16 and later. ### syslog-protocol The `syslog-protocol` flag specifies that incoming messages are expected to be formatted according to the new IETF syslog protocol standard (RFC5424), but without the frame header. Note that this flag is not needed for the `syslog` driver, which handles only messages that have a frame header. ### validate-utf8 The `validate-utf8` flag enables encoding-verification for messages. Prior to version 4.6, this flag worked only when parsing RFC3164 messages. Starting with version 4.6, it works also for RFC5424 and raw messages. For RFC5424-formatted messages, if the BOM character is missing, but the message is otherwise UTF-8 compliant, AxoSyslog automatically adds the BOM character to the message. The byte order mark (BOM) is a Unicode character used to signal the byte-order of the message text. ## follow-freq() | ---|--- Type: | number Default: | 1 _Description:_ Indicates that the source should be checked periodically. This is useful for files which always indicate readability, even though no new lines were appended. If this value is higher than zero, AxoSyslog will not attempt to use `poll()` on the file, but checks whether the file changed every time the `follow-freq()` interval (in seconds) has elapsed. Floating-point numbers (for example, `1.5`) can be used as well. ## hook-commands() _Description:_ This option makes it possible to execute external programs when the relevant driver is initialized or torn down. The `hook-commands()` can be used with all source and destination drivers with the exception of the `usertty()` and `internal()` drivers. Note The AxoSyslog application must be able to start and restart the external program, and have the necessary permissions to do so. For example, if your host is running AppArmor or SELinux, you might have to modify your AppArmor or SELinux configuration to enable AxoSyslog to execute external applications. ### Using `hook-commands()` when AxoSyslog starts or stops To execute an external program when AxoSyslog starts or stops, use the following options: #### `startup()` Type: | string ---|--- Default: | N/A _Description:_ Defines the external program that is executed as AxoSyslog starts. #### `shutdown()` Type: | string ---|--- Default: | N/A _Description:_ Defines the external program that is executed as AxoSyslog stops. ### Using the hook-commands() when AxoSyslog reloads To execute an external program when the AxoSyslog configuration is initiated or torn down, for example, on startup/shutdown or during a AxoSyslog reload, use the following options: #### `setup()` Type: | string ---|--- Default: | N/A _Description:_ Defines an external program that is executed when the AxoSyslog configuration is initiated, for example, on startup or during a AxoSyslog reload. #### `teardown()` Type: | string ---|--- Default: | N/A _Description:_ Defines an external program that is executed when the AxoSyslog configuration is stopped or torn down, for example, on shutdown or during a AxoSyslog reload. ### Example: Using hook-commands() with a network source In the following example, the `hook-commands()` is used with the `network()` driver and it opens an [iptables]( "https://en.wikipedia.org/wiki/Iptables") port automatically as AxoSyslog is started/stopped. The assumption in this example is that the `LOGCHAIN` chain is part of a larger ruleset that routes traffic to it. Whenever the AxoSyslog created rule is there, packets can flow, otherwise the port is closed. ``` source { network(transport(udp) hook-commands(           startup("iptables -I LOGCHAIN 1 -p udp --dport 514 -j ACCEPT")           shutdown("iptables -D LOGCHAIN 1")         )      ); }; ``` ## idle-timeout() | ---|--- Accepted values: | number [seconds] Default: | `0` (disabled) Available in AxoSyslog 4.9 and later. If set, AxoSyslog closes the client connection if no data is received for the specified amount of time (in seconds). ## keep-timestamp() | ---|--- Type: | yes or no Default: | yes _Description:_ Specifies whether AxoSyslog should accept the timestamp received from the sending application or client. If disabled, the time of reception will be used instead. This option can be specified globally, and per-source as well. The local setting of the source overrides the global option if available. Warning To use the `S_` macros, the `keep-timestamp()` option must be enabled (this is the default behavior of AxoSyslog). ## log-fetch-limit() | ---|--- Type: | number Default: | 100 _Description:_ The maximum number of messages fetched from a source during a single poll loop. The destination queues might fill up before flow-control could stop reading if `log-fetch-limit()` is too high. ## log-iw-size() | ---|--- Type: | number Default: | 10000 _Description:_ The size of the initial window, this value is used during flow control. Make sure that `log-iw-size()` is larger than the value of `log-fetch-limit()`. Warning ```

If you change the value of log-iw-size() and keep-alive() is enabled, the change will affect only new connections, the log-iw-size() of kept-alive connections will not change. To apply the new log-iw-size() value to every connection, restart the syslog-ng service. A simple configuration reload is NOT sufficient.

``` If the source is receiving data using the UDP protocol, always [restart the `syslog-ng` service](../../../docs/axosyslog-core/quickstart/managing-and-checking-linux/index.md#restart-axosyslog) after changing the value of `log-iw-size()` for the changes to take effect. When using wildcards in the filenames, AxoSyslog attempts to read `log-fetch-limit()` number of messages from each file. For optimal performance, make sure that `log-iw-size()` is greater than `log-fetch-limit()*max-files()`. Note that to avoid performance problems, if `log-iw-size()/max-files()` is smaller than 100, AxoSyslog automatically sets `log-iw-size()` to `max-files()*100`. ### Example: Initial window size of file sources If `log-fetch-limit()` is 100, and your wildcard file source has 200 files, then `log-iw-size()` should be at least 20000. ## log-msg-size() | ---|--- Type: | number (bytes) Default: | Use the global `log-msg-size()` option, which defaults to `65536` (64 KiB). _Description:_ Maximum length of an incoming message in bytes. This length includes the entire message (the data structure and individual fields). The maximal value that can be set is 268435456 bytes (256 MiB). For messages using the IETF-syslog message format (RFC5424), the maximal size of the value of an SDATA field is 64 KiB. Note In most cases, `log-msg-size()` does not need to be set higher than 10 MiB. For details on how encoding affects the size of the message, see [Message size and encoding](../../../docs/axosyslog-core/chapter-concepts/concepts-message-representation/index.md). You can use human-readable units when setting configuration options. For details, see[Notes about the configuration syntax](../../../docs/axosyslog-core/chapter-configuration-file/configuration-syntax-notes/index.md). Uses the value of the [global option](../../../docs/axosyslog-core/chapter-global-options/reference-options/index.md#global-option-log-msg-size) if not specified. ## log-prefix() (DEPRECATED) | ---|--- Type: | string Default: | _Description:_ A string added to the beginning of every log message. It can be used to add an arbitrary string to any log source, though it is most commonly used for adding `kernel:` to the kernel messages on Linux. Note This option is deprecated. Use `program-override` instead. ## max-files() | ---|--- Type: | integer Default: | 100 _Description:_ Limits the number of files that the wildcard-file source monitors. When using wildcards, AxoSyslog monitors every matching file (up to the limit set in the `max-files()` option), and can receive new log messages from any of the files. However, monitoring (polling) many files (that is, more than ten) has a significant overhead and may affect performance. On Linux this overhead is not so significant, because AxoSyslog uses the inotify feature of the kernel. Set the `max-files()` option at least to the number of files you want to monitor. If the wildcard-file source matches more files than the value of the `max-files()` option, it is random which files will AxoSyslog actually monitor. The default value of `max-files()` is 100. ## monitor-method() | ---|--- Type: | `auto Default: | `auto` _Description:_ If the platform supports inotify, AxoSyslog uses it automatically to detect changes to the source files. If inotify is not available, AxoSyslog polls the files as set in the `follow-freq()` option. To force AxoSyslog poll the files even if inotify is available, set this option to `poll`. ## multi-line-garbage() | ---|--- Type: | regular expression Default: | empty string _Description:_ Use the `multi-line-garbage()` option when processing multi-line messages that contain unneeded parts between the messages. Specify a string or regular expression that matches the beginning of the unneeded message parts. If the `multi-line-garbage()` option is set, AxoSyslog ignores the lines between the line matching the `multi-line-garbage()` and the next line matching `multi-line-prefix()`. See also the `multi-line-prefix()` option. When receiving multi-line messages from a source when the `multi-line-garbage()` option is set, but no matching line is received between two lines that match `multi-line-prefix()`, AxoSyslog will continue to process the incoming lines as a single message until a line matching `multi-line-garbage()` is received. To use the `multi-line-garbage()` option, set the `multi-line-mode()` option to `prefix-garbage`. Warning If the `multi-line-garbage()` option is set, AxoSyslog discards lines between the line matching the `multi-line-garbage()` and the next line matching `multi-line-prefix()`. ## multi-line-mode() | ---|--- Type: | `indented`, `prefix-garbage`, `prefix-suffix`, `regexp`, `smart` Default: | empty string _Description:_ Use the `multi-line-mode()` option when processing multi-line messages. The AxoSyslog application provides the following methods to process multi-line messages: * `indented`: The `indented` mode can process messages where each line that belongs to the previous line is indented by whitespace, and the message continues until the first non-indented line. For example, the Linux kernel (starting with version 3.5) uses this format for `/dev/log`, as well as several applications, like Apache Tomcat. ``` source s_tomcat { file("/var/log/tomcat/xxx.log" multi-line-mode(indented)); }; ``` * `prefix-garbage`: The _prefix-garbage_ mode uses a string or regular expression (set in `multi-line-prefix()`) that matches the beginning of the log messages, ignores newline characters from the source until a line matches the regular expression again, and treats the lines between the matching lines as a single message. For details on using `multi-line-mode(prefix-garbage)`, see the `multi-line-prefix()` and `multi-line-garbage()` options. * `prefix-suffix`: The `prefix-suffix` mode uses a string or regular expression (set in `multi-line-prefix()`) that matches the beginning of the log messages, ignores newline characters from the source until a line matches the regular expression set in `multi-line-suffix()`, and treats the lines between `multi-line-prefix()` and `multi-line-suffix()` as a single message. Any other lines between the end of the message and the beginning of a new message (that is, a line that matches the `multi-line-prefix()` expression) are discarded. For details on using `multi-line-mode(prefix-suffix)`, see the `multi-line-prefix()` and `multi-line-suffix()` options. The `prefix-suffix` mode is similar to the `prefix-garbage` mode, but it appends the garbage part to the message instead of discarding it. * `smart`: The `smart` mode recognizes multi-line data backtraces even if they span multiple lines in the input. The backtraces are converted to a single log message for easier analysis. Backtraces for the following programming languages are recognized : Python, Java, JavaScript, PHP, Go, Ruby, and Dart. `smart` mode is available in AxoSyslog version 4.2 and newer. The regular expressions to recognize these programming languages are specified in an external file called `/usr/share/syslog-ng/smart-multi-line.fsm` (installation path depends on configure arguments), in a format that is described in that file. Note To format multi-line messages to your individual needs, consider the following: * To make multi-line messages more readable when written to a file, use a template in the destination and instead of the `${MESSAGE}` macro, use the following: `$(indent-multi-line ${MESSAGE})`. This expression inserts a tab after every newline character (except when a tab is already present), indenting every line of the message after the first. For example: ``` destination d_file { file ("/var/log/messages" template("${ISODATE} ${HOST} $(indent-multi-line ${MESSAGE})\n") ); }; ``` For details on using templates, see [Templates and macros](../../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/configuring-macros/index.md). * To actually convert the lines of multi-line messages to single line (by replacing the newline characters with whitespaces), use the `flags(no-multi-line)` option in the source. ## multi-line-prefix() | ---|--- Type: | regular expression starting with the ^ character Default: | empty string _Description:_ Use the `multi-line-prefix()` option to process multi-line messages, that is, log messages that contain newline characters (for example, Tomcat logs). Specify a string or regular expression that matches the beginning of the log messages (always start with the `^` character). Use as simple regular expressions as possible, because complex regular expressions can severely reduce the rate of processing multi-line messages. If the `multi-line-prefix()` option is set, AxoSyslog ignores newline characters from the source until a line matches the regular expression again, and treats the lines between the matching lines as a single message. See also the `multi-line-garbage()` option. Note To format multi-line messages to your individual needs, consider the following: * To make multi-line messages more readable when written to a file, use a template in the destination and instead of the `${MESSAGE}` macro, use the following: `$(indent-multi-line ${MESSAGE})`. This expression inserts a tab after every newline character (except when a tab is already present), indenting every line of the message after the first. For example: ``` destination d_file { file ("/var/log/messages" template("${ISODATE} ${HOST} $(indent-multi-line ${MESSAGE})\n") ); }; ``` For details on using templates, see [Templates and macros](../../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/configuring-macros/index.md). * To actually convert the lines of multi-line messages to single line (by replacing the newline characters with whitespaces), use the `flags(no-multi-line)` option in the source. ### Example: Processing Tomcat logs The log messages of the Apache Tomcat server are a typical example for multi-line log messages. The messages start with the date and time of the query in the `YYYY.MM.DD HH:MM:SS` format, as you can see in the following example. ``` 2010.06.09. 12:07:39 org.apache.catalina.startup.Catalina start SEVERE: Catalina.start: LifecycleException: service.getName(): "Catalina"; Protocol handler start failed: java.net.BindException: Address already in use null:8080 at org.apache.catalina.connector.Connector.start(Connector.java:1138) at org.apache.catalina.core.StandardService.start(StandardService.java:531) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) at org.apache.catalina.startup.Catalina.start(Catalina.java:583) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.commons.daemon.support.DaemonLoader.start(DaemonLoader.java:177) 2010.06.09. 12:07:39 org.apache.catalina.startup.Catalina start INFO: Server startup in 1206 ms 2010.06.09. 12:45:08 org.apache.coyote.http11.Http11Protocol pause INFO: Pausing Coyote HTTP/1.1 on http-8080 2010.06.09. 12:45:09 org.apache.catalina.core.StandardService stop INFO: Stopping service Catalina ``` To process these messages, specify a regular expression matching the timestamp of the messages in the `multi-line-prefix()` option. Such an expression is the following: ``` source s_file{file("/var/log/tomcat6/catalina.2010-06-09.log" follow-freq(0) multi-line-mode(regexp) multi-line-prefix("[0-9]{4}\.[0-9]{2}\.[0-9]{2}\.") flags(no-parse));}; }; ``` Note that `flags(no-parse)` is needed to prevent AxoSyslog trying to interpret the date in the message. ## multi-line-suffix() | ---|--- Type: | regular expression Default: | empty string _Description:_ Use the `multi-line-suffix()` option when processing multi-line messages. Specify a string or regular expression that matches the end of the multi-line message. To use the `multi-line-suffix()` option, set the `multi-line-mode()` option to `prefix-suffix`. See also the `multi-line-prefix()` option. ## pad-size() | ---|--- Type: | number Default: | 0 _Description:_ Specifies input padding. Some operating systems (such as HP-UX) pad all messages to block boundary. This option can be used to specify the block size. The AxoSyslog application will pad reads from the associated device to the number of bytes set in `pad-size()`. Mostly used on HP-UX where `/dev/log` is a named pipe and every write is padded to 2048 bytes. If `pad-size()` was given and the incoming message does not fit into `pad-size()`, AxoSyslog will not read anymore from this pipe and displays the following error message: ``` Padding was set, and couldn't read enough bytes ``` ## program-override() | ---|--- Type: | string Default: | _Description:_ Replaces the ${PROGRAM} part of the message with the parameter string. For example, to mark every message coming from the kernel, include the `program-override("kernel")` option in the source containing `/proc/kmsg`. ## recursive() | ---|--- Type: | `yes` or `no` Default: | `no` _Description:_ When enabled, AxoSyslog monitors every subdirectory of the path set in the [base-dir()](../../../docs/axosyslog-core/chapter-sources/configuring-sources-wildcard-file/reference-source-wildcard-file/index.md#source-wildcard-file-base-dir) option, and reads log messages from files with matching filenames. The `recursive` option can be used together with wildcards in the filename. Warning If you use multiple `wildcard-file()` sources in your configuration, make sure that the files and folders that match the wildcards do not overlap. That is, every file and folder should belong to only one file source. Monitoring a file from multiple wildcard sources can lead to data loss. ## Example: Monitoring multiple directories The following example reads files having the `.log` extension from the `/var/log/` directory and its subdirectories, including for example, the `/var/log/apt/history.log` file. ``` source s_file_subdirectories { wildcard-file( base-dir("/var/log") filename-pattern("*.log") recursive(yes) follow-freq(1) log-fetch-limit(100) ); }; ``` ## tags() | ---|--- Type: | string Default: | _Description:_ Label the messages received from the source with custom tags. Tags must be unique, and enclosed between double quotes. When adding multiple tags, separate them with comma, for example, `tags("dmz", "router")`. This option is available only in version 3.1 and later. ## time-zone() | ---|--- Type: | name of the timezone, or the timezone offset Default: | _Description:_ The default timezone for messages read from the source. Applies only if no timezone is specified within the message itself. The timezone can be specified by using the name, for example, `time-zone("Europe/Budapest")`), or as the timezone offset in +/-HH:MM format, for example, `+01:00`). On Linux and UNIX platforms, the valid timezone names are listed under the `/usr/share/zoneinfo` directory. Last modified August 6, 2025: [Typo fix (8c912c8)]()