ATMSIGD.CONF(4)

✨ ATMSIGD.CONF ✨

okay bestie, so this is the atmsigd.conf page, and yes it lives in section 4 of the manual (file formats, iykyk). it's literally the config file for the ATM signaling demon and it's giving very "small file, big responsibilities" energy. let's get into it 💅

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🎀 SYNOPSIS 🎀

/etc/atmsigd.conf

just the path. that's the whole vibe. slay.

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🦋 DESCRIPTION 🦋

atmsigd.conf holds configuration data for atmsigd. and the timing?? immaculate: atmsigd reads atmsigd.conf after parsing the command line options, and before connecting to the ATM network. so it's like the little pre-game routine before the big entrance. periodt.

Configuration parameters are arranged in functional groups. to set a parameter you gotta say three things: the name of the group, the name of the parameter, and the parameter value(s). like, for example:

sig level debug

and that right there decreases the logging threshold for messages related to signaling to the debug level. iconic. the following options are recognized:

• debug dump path — says which directory atmsigd writes its status and trace dumps to. if tracing isn't enabled yet, the trace size gets automatically set to a (small) default value. cute little starter size 💖
• debug level level — sets the default debug level to level. level can be any of debug, info, warn, error, and fatal. only messages with the same or a higher priority than the debug level get printed. and heads up bestie: the command-line option -d generates even more output (like, hexdumps of all packets passing between atmsigd and the network) than debug level debug does. so -d is the max volume setting fr fr 😭
• debug log path — specifies the file atmsigd writes logging messages to. when you use the special file name syslog, messages are send to the system logger instead. log messages go to standard output if no log file is specified. and writing to standard output can also be explicitly requested by using the special file name stderr. so stderr is the "yes i really mean stdout" button, which is honestly a whole mood 🫶
• debug trace [number] — enables tracing and optionally sets the number of entries that should be kept in the trace buffer. if you omit number, a (small) default is used. no notes.
• io level level — sets the debug level for IO-related messages to level.
• io max_rate rate — sets the rate to signal if an application requests the "maximum". check qos(7) for the syntax to use when expressing the rate. the default maximum rate is 353207 cells/second (OC3). (note that the value of max_rate does not constrain the rates an application can explicitly request — it's a suggestion vibe, not a fence.)
• io qos qos — configures the signaling VC to use the specified QOS (peep qos(7) for the syntax). by default, UBR at link speed is used on the signaling VC.
• io vc [itf.]vpi.vci — uses the specified VC for signaling messages instead of the usual 0.0.5. giving main character VC energy ✨
• saal level level — sets the debug level for messages related to SAAL (i.e. SSCF and SSCOP) to level.
• sig level level — sets the debug level for messages related to signaling (Q.2931 or ISP) to level.
• sig mode mode — sets the mode of operation. the following modes are available: user for the user side, network for the network side, and switch for operation in a switch. the default behaviour is user. (user is the default, she's humble like that 💜)
• sig uni30 — use UNI 3.0 signaling. if specified together with sig uni31, this option sets UNI 3.1 signaling with a few backwards-compatibility extensions. so they're a duo, not a rivalry 🎀
• sig uni31 — use UNI 3.1 signaling. this option can be combined with sig uni30 (see above).
• sig uni40 — use UNI 4.0 signaling. this option can be combined with sig q.2963.1 (see below).
• sig q.2963.1 — enable peak cell rate renegotiation. this option is only available with UNI 4.0 signaling. exclusive collab, no plus-ones 💅
• sig vpci vpci itf itf — sets up a very simplistic type of routing. all calls with VPCI values equal to or greater than vpci will be routed to itf, and their VPI values will be set to the signaled VPCI minus vpci. multiple sig vpci entries can be used to support an arbitrary number of interfaces. example: with sig vpci 4 itf 1, a call signaled for VPCI/VCI 0.x is routed to 0.0.x, a call signaled for 6.y is routed to 1.2.y, etc. math girlies rise 🧚
• policy level level — sets the debug level for messages related to policy decisions to level.
• policy decision direction address — takes the specified decision for calls from or to address. decision can be either allow or reject. direction is either from or to. the address may be wildcarded by prepending a slash and the number of significant bits (NSAP) or digits (E.164). the rules are searched in the order in which they appear in atmsigd.conf until the first match. if no rule matches, the call is allowed. so like, first match wins, and the house default is "sure babe, come in" 🫶
• entity [itf.]vpi.vci { options ... } — activates a signaling entity on that specific VC. multiple entity clauses can appear in the same configuration. when using entity, the option io vc is not available. entity is optionally followed by the following options, enclosed in curly braces: vpci (corresponds to sig vpci), mode (corresponds to sig mode), qos (corresponds to vc qos), route, and default. the last two options determine how outbound calls are routed. the route option is followed by an address in the format used for addresses in policy. if no route entry matches the called party number of an outbound call, the entry marked with default is selected.

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🌸 grouping your parameters (the curly brace shortcut) 🌸

when you're setting multiple parameters in the same group, you don't have to repeat the group name if it's followed by the parameters in curly braces. example:

debug {
    level warn
    dump /var/tmp
    log syslog
    trace 100
}

look at that formatting. ate and left no crumbs 💅

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⭐ little syntax rules ⭐

line breaks can be inserted in atmsigd.conf wherever spaces or tabs are allowed. everything between a # and the end of the line is considered a comment. and the # character cannot be escaped — no sneaky backslash rescue, it's just a comment forever, sorry bestie 💀

🚨 also important: if an option is specified in atmsigd.conf and on the command line, the command line has priority. command line is the main character here, no cap.

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💀 COMPATIBILITY 💀

certain options used by past versions of atmsigd but no longer documented on the man page are still recognized and supported, but they also yield a warning message. future versions of atmsigd will not recognize those options. so it's giving "we still love you but you're on borrowed time" 🙈

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👑 AUTHOR 👑

Werner Almesberger, EPFL ICA <Werner.Almesberger@epfl.ch>

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🌈 SEE ALSO 🌈

• atmsigd(8)
• qos(7)
• syslogd(8)

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and that's the whole page bestie!! go configure something iconic 💖✨ this was brought to you by the Linux manual gang, version dated March 19, 2000 — yes, the year 2000, she's vintage, she's timeless, she's still serving. bye ily 🎀🦋