We just did a quick trip to the marsh (just about an hour base-to-base) to revive S8's networking. I got it running with: su; ifdown eth1; ifup eth1. I tried switching the USB positions of the stick and the modem, but they don't fit the other way.
After talking with Gordon, I'll try to implement his old script to check networking and do ifdown/up to attempt to revive. 2 trips to S8 in a day is fun, but I don't want to make a habit of it.
4 Comments
Gordon Maclean
The script is /home/daq/isfs/bin/net_check.sh on every DSM. Gary may have a better idea, or want to make changes to it.
Probably should run it from root's crontab to avoid having to use sudo.
Since /home/daq/isfs/bin isn't in root's PATH, you could add it at the top of root's crontab:
PATH=$PATH:/home/daq/isfs/bin
or
PATH=/usr/bin:/bin:/usr/sbin:/sbin:/home/daq/isfs/bin
The cell interface is eth1? It also checks that the address associated with the interface is in a subnet.
Assuming the subnet is 192.168.1, the command would be:
net_check.sh eth1 192.168.1 www.google.com
Instead of www.google.com you could ping a static IP of 8.8.8.8
Gary Granger
If S8 does not have an external antenna, with a ground plane, then it might be worth adding one. For ground planes at a couple of sites we used some angle iron from the trailer, but we also considered the metal bookends which are probably still sitting near the microwave, unless you want to go to the hardware store and buy some actual sheet metal.
The first few days I was there with Steve and Kurt, we added external antennas to a couple of the more problematic sites. In the three weeks after that, I think we only fiddled with a cell modem once to get it to reconnect. S8 in particular has been up solid from Aug 21 to Sep 20. It even rebooted 4 times over that period, the last time before today was Sep 10. So it seems odd that suddenly now it would start getting unreliable. Is there possibly anything else peculiar about the timing?
net_check.sh seems like a reasonable thing to try, I don't think it would hurt anything.
Steve Oncley AUTHOR
OK. net_check is now enabled on S8. (Thanks to Gary for the edit: /bin/sh -> /bin/bash to get this script working.) When I've tested it, it always does an ifdown/ifup (but the connection stays up). I had expected it to do the ifdown/ifup only when google can't ping...
P.S. After a nice offline exchange with Gordon, I changed the subnet in this crontab. So far, this is only enabled on S8.
Gary Granger
There were still a few bugs. I fixed the crontab command line to remove an extra eth1, and the PATH=$PATH setting in the crontab file was not working, it left /usr/bin off the path which meant the script could never work when called from cron. Finally, the net_check.sh expected the IP state (UP or DOWN) to be on line 3 in ifconfig, but for eth1 it is on line 4 because of the existence of an extra IPV6 address on eth1. That's why it was always acting as if the interface was down, even when called from the command line. I've made a temporary fix to the script, so for now it appears to be working, even from cron, but I'll try to make a better fix and commit the changes.