System Reboots

In this sample example, we monitor and report system reboots.

The SysReboot script might send an alert message like the following:

                                PIKT ALERT
                         Thu Oct 11 12:32:02 2007
                                  vienna

CRITICAL:
    SysReboot
        Scan the 'last' command output for signs of recent system reboots

        reboot   system boot  2.6.17-gentoo-r4 Thu Oct 11 11:58          (00:33)   

The script follows.

SysReboot

        init
                status =piktstatus
                level =piktlevel
                task "Scan the 'last' command output for signs of recent system reboots"
                input proc "last | =head"
                filter "=egrep 'system boot|shutdown'"
                dat $dow  $-4           // not currently used
                dat $mon  $-3
                dat $date $-2
                dat $time $-1

        begin
                set #first = #true()
                // ensure that we set $mdtprev anew in the current script
                // run for recall as %mdtprev in the next script run (the
                // 'set $mdtprev' below is conditional)
                if #defined(%mdtprev)
                        set $mdtprev = %mdtprev
                else
                        set $mdtprev = ""
                endif

        rule
                set #daynumber_reboot = #daynumber($dow)

        rule    // since the "last" command output doesn't show the year,
                // we need a way to determine if we are wrapping around
                // to previous years; keeping track of month turnovers is
                // a kludgy way to do this
                set #monthnumber_reboot = #monthnumber($mon)
                if #monthnumber_reboot != @monthnumber_reboot
                        =incr(#monthturnovers)
                endif

        rule
                do #split($time, ":")
                set #hour_reboot = #val($1)

        rule    // ignore scheduled reboots
                if =reboot_period(#daynumber_reboot, #hour_reboot)
                        next
                fi

        rule
                // using =set_lineage to determine the age gives better
                // results than the following:
                // if #age($mon,$date,$time) <= 1
                =set_lineage($inline)
                if    #lineage == #err()
                   || #lineage < 0
                   || #monthturnovers > 1       // are at least 2 months
                                                // into the past
                        next    // not in current year, or bad input line
                endif
                // since this alarm is run daily, only report reboots in the
                // last 24 hours
                if #lineage < =secs_in_day
                        set $mdt = "$mon $date $time"
                        if    #defined(%mdtprev)
                           && %mdtprev =~ $mdt
                                quit
                        endif
                        output mail $inline
                        if #first
                                set #first = #false()
                                set $mdtprev = $mdt
                        else
                                set $mdtprev .= " $mdt"
                        endif
                endif

This is just one program example.  You could add rules, or write new scripts, for example to:  remove /var/crash files after a reboot, log uptime data, etc.

For more examples, see Samples.