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Commands Reference, Volume 2

gdc Command

Purpose

Provides an operational user interface for gated.

Syntax

gdc [ -q ] [ -n ] [ -c coresize ] [ -f filesize ] [ -m datasize ] [ -s stacksize ] [ -t seconds ] Subcommands

Description

The gdc command provides a user-oriented interface for the operation of the gated routing daemon. It provides support for:

The gdc command can reliably determine gated's running state and produces a reliable exit status when errors occur, making it advantageous for use in shell scripts which manipulate gated. Commands executed using gdc and, optionally, error messages produced by the execution of those commands, are logged via the same syslogd facility which gated itself uses, providing an audit trail of operations performed on the daemon.

Flags

-n Runs without changing the kernel forwarding table. This is useful for testing, and when operating as a route server which does no forwarding.
-q Runs quietly. With this flag informational messages which are normally printed to the standard output are suppressed and error messages are logged with syslogd instead of being printed to the standard error output. This is convenient when running gdc from a shell script.
-t seconds Specifies the time in seconds that gdc waits for gated to complete certain operations, in particular at termination and startup. By default this value is set to 10 seconds.
-c coresize Sets the maximum size of a core dump a gated started with gdc produces. This is useful on systems where the default maximum core dump size is too small for gated to produce a full core dump on errors.
-f filesize Sets the maximum file size a gated started with gdc will produce. Useful on systems where the default maximum file dump size is too small for gated to produce a full state dump when requested.
-m datasize Sets the maximum size of the data segment of a gated started with gdc. Useful on systems where the default data segment size is too small for gated to run.
-s stacksize Sets the maximum size of stack of a gated started with gdc. Useful on systems where the default maximum stack size is too small for gated to run.

Subcommands

The following subcommands cause signals to be delivered to gated for various purpose:

COREDUMP Sends an abort signal to gated, causing it to terminate with a core dump.
dump Signals gated to dump its current state into the file /var/tmp/gated_dump.
interface Signals gated to recheck the interface configuration. gated normally does this periodically in any event, but the facility can be used to force the daemon to check interface status immediately when changes are known to have occured.
KILL Causes gated to terminate ungracefully.
reconfig Signals gated to reread its configuration file, reconfiguring its current state as appropriate.
term Signals gated to terminate after shutting down all operating routing protocols gracefully. Executing this command a second time causes gated to terminate even if some protocols have not yet fully shut down.
toggletrace Causes tracing to be suspended, and if gated is currently tracing to a file, closes the trace file. If gated tracing is current suspended, this subcommand causes the trace file to be reopened and tracing initiated. This is useful for moving trace files.

The following subcommands perform operations related to configuration files:

checkconf Check /etc/gated.conf for syntax errors. This is usefully done after changes to the configuration file but before sending a reconfig signal to the currently running gated, to ensure that there are no errors in the configuration which would cause the running gated to terminate on reconfiguration. When this command is used, gdc issues an informational message indicating whether there were parse errors or not, and if so saves the error output in a file for inspection.
checknew Like checkconf except that the new configuration file, /etc/gated.conf+, is checked instead.
newconf Move the /etc/gated.conf+ file into place as /etc/gated.conf, retaining the older versions of the file as described above. gdc will decline to do anything when given this command if the new configuration file doesn't exist or otherwise looks suspect.
backout Rotate the configuration files in the newer direction, in effect moving the old configuration file to /etc/gated.conf. The command will decline to perform the operation if /etc/gated.conf- doesn't exist or is zero length, or if the operation would delete an existing, non-zero length /etc/gated.conf+ file.
BACKOUT Perform a backout operation even if /etc/gated.conf+ exists and is of non-zero length.
modeconf Set all configuration files to mode 664, owner root, group system.
createconf If /etc/gated.conf+ does not exist, create a zero length file with the file mode set to 664, owner root, group system.

The following subcommands provide support for starting and stopping gated, and for determining its running state:

running Determine if gated is currently running. This is done by checking to see if gated has a lock on the file containing its pid, if the pid in the file is sensible and if there is a running process with that pid. Exits with zero status if gated is running, non-zero otherwise.
start Start gated. The command returns an error if gated is already running. Otherwise it executes the gated binary and waits for up to the delay interval (10 seconds by default, as set with the -t option otherwise) until the newly started process obtains a lock on the pid file. A non-zero exit status is returned if an error is detected while executing the binary, or if a lock is not obtained on the pid file within the specified wait time.
stop Stop gated, gracefully if possible, ungracefully if not. The command returns an error (with non-zero exit status) if gated is not currently running. Otherwise it sends a terminate signal to gated and waits for up to the delay interval (10 seconds by default, as specified with the -t option otherwise) for the process to exit. Should gated fail to exit within the delay interval it is then signaled again with a second terminate signal. Should it fail to exit by the end of the second delay interval it is signalled for a third time with a kill signal. This should force immediate termination unless something is very broken. The command terminates with zero exit status when it detects that gated has terminated, non-zero otherwise.
restart If gated is running it is terminated via the same procedure as is used for the stop command above. When the previous gated terminates, or if it was not running prior to command execution, a new gated process is executed using the procedures described for the start command above. A non-zero exit status is returned if any step in this procedure appears to have failed.

The following subcommands allow the removal of files created by the execution of some of the commands above:

rmcore Removes any existing gated core dump file.
rmdump Removes any existing gated state dump file.
rmparse Removes the parse error file generated when a checkconf or checknew command is executed and syntax errors are encountered in the configuration file being checked.

The following subcommand allows the version information for gated to be displayed:

version Show the version information for gated. gated cannot already be running at the time this command is executed. No options of gdc are used with this command.

By default gated obtains its configuration from a file normally named /etc/gated.conf. The gdc program also maintains several other versions of the configuration file, in particular named:

/etc/gated.conf+ The new configuration file. When gdc is requested to install a new configuration file, this file is renamed /etc/gated.conf.
/etc/gated.conf- The old configuration file. When gdc is requested to install a new configuration file, the previous /etc/gated.conf is renamed to this name.
/etc/gated.conf-- The really old configuration file. gdc retains the previous old configuration file under this name.

Files

/usr/sbin/gated The gated binary.
/etc/gated.conf Current gated configuration file.
/etc/gated.conf+ Newer configuration file.
/etc/gated.conf- Older configuration file
/etc/gated.conf-- Much older configuration file
/etc/gated.pid Where gated stores its pid.
/var/tmp/gated_dump gated's state dump file
/var/tmp/gated.log Where config file parse errors go.

Related Information

The gated Daemon, and syslogd Daemon.

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