# default-network-drivers() source options The `systemd-journal()` driver has the following options. ## ca-dir() | ---|--- Accepted values: | Directory name Default: | none _Description:_ The name of a directory that contains a set of trusted CA certificates in PEM format. The CA certificate files have to be named after the 32-bit hash of the subject’s name. This naming can be created using the c_rehash utility in openssl. For an example, see [Configuring TLS on the AxoSyslog clients](../../../docs/axosyslog-core/chapter-encrypted-transport-tls/tls-serverauth/procedure-configuring-tls-client/index.md). The AxoSyslog application uses the CA certificates in this directory to validate the certificate of the peer. This option can be used together with the optional `ca-file()` option. ## ca-file() | ---|--- Accepted values: | File name Default: | empty _Description:_ Optional. The name of a file that contains a set of trusted CA certificates in PEM format. The AxoSyslog application uses the CA certificates in this file to validate the certificate of the peer. Example format in configuration: ``` ca-file("/etc/pki/tls/certs/ca-bundle.crt") ``` Note The `ca-file()` option can be used together with the `ca-dir()` option, and it is relevant when `peer-verify()` is set to other than `no` or `optional-untrusted`. ## 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’s considered to be part of the log message. You can also enable this behavior globally using the [`check-program` global option](../../../docs/axosyslog-core/chapter-global-options/reference-options/index.md#global-option-check-program). ### 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. ## log-iw-size() | ---|--- Type: | number Default: | 100 _Description:_ Specifies the source window size - the maximum number of in-flight messages permitted by the source before flow control is enforced. This only applies when `flow-control` is enabled. 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](../../../docs/axosyslog-core/quickstart/managing-and-checking-linux/index.md#restart-axosyslog). 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. Note that when using `disk-buffer()`, the messages stored on disk are not included in the window size calculation. For details about the effects of this parameter, see [Managing incoming and outgoing messages with flow-control](../../../docs/axosyslog-core/chapter-routing-filters/concepts-flow-control/index.md). ## 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. ## max-connections() | ---|--- Type: | number Default: | 10 _Description:_ Specifies the maximum number of simultaneous connections. Doesn’t affect UDP-based traffic, which is always treated as a single connection. Note that the total number of connections the `default-network-drivers()` source can use is 3*`max-connections()`, because this value applies to the `network(tcp)`, `syslog(tcp)`, and `syslog(tls)` connections individually. ## rfc5424-tcp-port() | ---|--- Type: | number Default: | 601 _Description:_ The TCP port number where the `default-network-drivers()` source receives RFC5424-formatted (IETF-syslog) messages. ## rfc5424-tls-port() | ---|--- Type: | number Default: | 6514 _Description:_ The TCP port number where the `default-network-drivers()` source receives RFC5424-formatted (IETF-syslog), TLS-encrypted messages. Warning To receive messages using a TLS-encrypted connection, you must set the `tls(key-file() cert-file())` options of the `default-network-drivers()` source. For example: ``` source s_network { default-network-drivers( tls( key-file("/path/to/ssl-private-key") cert-file("/path/to/ssl-cert") ) ); }; ``` ## tcp-port() | ---|--- Type: | number Default: | 514 _Description:_ The TCP port number where the `default-network-drivers()` source receives RFC3164-formatted (BSD-syslog) messages. ## tls() | ---|--- Type: | tls options Default: | n/a _Description:_ This option sets various options related to TLS encryption, for example, key/certificate files and trusted CA locations. TLS can be used only with tcp-based transport protocols. For details, see [TLS options](../../../docs/axosyslog-core/chapter-encrypted-transport-tls/tlsoptions/index.md). ## udp-port() | ---|--- Type: | number Default: | 514 _Description:_ The UDP port number where the `default-network-drivers()` source receives RFC3164-formatted (BSD-syslog) messages. Last modified August 28, 2024: [Formatting fixes (c26e237b)]()