# 7.2. How to interpret the system's log

## 7.2.1. Serial line is looped back

Short answer: You haven't started the PPP software on the peer system.

See a posting from Al Longyear on http://www.dejanews.com/getdoc.xp?AN=184945314 for a more detailed explanation.

## 7.2.2. Signal 15

If you see the following lines you've probably just received a timeout error from kppp, too. kppp has been waiting for the PPP interface to come up and gave up after the specified timeout. pppd was signaled to shut down with signal number 15, i.e. SIGTERM.

     pppd[26921]: pppd 2.3.5 started by me, uid 500
     pppd[26921]: Using interface ppp0
     pppd[26921]: Connect: ppp0 <--> /dev/ttyS0
     pppd[26921]: Terminating on signal 15.
     pppd[26921]: Connection terminated.
     pppd[26921]: Exit.

## 7.2.3. Receive serial link is not 8-bit clean

The PPP daemon is alarmed by the fact that all data it receives has bit 8 set to zero. In most cases this simply indicates that the remote PPP server isn't running yet. You might be still confronted with a login prompt that echoes back all data sent by your pppd.

## 7.2.4. can't locate module ppp-compress

Do you get the following messages ?

     modprobe: can't locate module ppp-compress-21
     modprobe: can't locate module ppp-compress-26
     modprobe: can't locate module ppp-compress-24

Just add the lines

     alias ppp-compress-21 bsd_comp
     alias ppp-compress-24 ppp_deflate
     alias ppp-compress-26 ppp_deflate

to your /etc/conf.modules file.