PPPD is not retrying to connect

[Patrick B.]

Hi,

in our setup we are using PPPD to connect to a 3G network. On some sites we have a bad and varying signal quality, which makes that sometimes the carrier is lost during some hours.

In some cases which we haven’t yet exactly pinned down how to reproduce – something with a very low signal at boot-time and then losing it while connecting, we fail to connect. In this case the last message is “local2.info chat[2667]: Failed (NO CARRIER)”. If this happens, pppd seems to never ever try to reconnect again.

The process is still running and to force a new attempt to connect we need to kill pppd and run the dial-in manually – which of course is problematic for a remote site.

Is this a known problem? We basically followed the instruction from here

Start Cell Connection on Boot

And it works, when the signal quality is good enough. Should we put in a place watchdog? How do you handle this kind of problems on your routers?

Thanks,
—
Patrick.

• This topic was modified 7 years, 10 months ago by Patrick B..

[Jeff Hatch]

Patrick,

I’m pretty sure that pppd doesn’t automatically redial/reconnect. You will need to check the connection by pinging 8.8.8.8 or something like that, and if the ping fails restart pppd.

Jeff

[Patrick B.]

Jeff,

Adding the persist option to /var/config/ppp/options makes pppd reconnect automatically when the connection is lost. This works quite well, except in the situation I’m describing.

—
Patrick.

[Jeff Hatch]

Patrick,

We’ve found that we’ve had to still test our Internet connectivity even though pppd is up and has carrier and connectivity with the tower. We basically ping 8.8.8.8 and if over a given amount of time the ping still isn’t working we restart pppd.

Jeff

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