I understand that this a upstream list and most readers are interested in the bleeding edge. However, I have to support some systems for "naive" users and I prefer to use a plain vanilla distribution as long as possible. So please bear with my question regarding versions straight from the museum...
On Ubuntu 10.04 (long time support) they have nm version 0.8-0ubuntu3 The USB modem in use is a Nokia CS-17. (I know that if you search for trouble, you select a 3G USB modem. Unfortunately this variant is really by orders of magnitude cheaper in this case than anything more reliable.) The good news is that the CS-17 works even with that old software. The bad news is that it's completely unreliable. Some 30%-50% of the connection attempts just fail. Unfortunately the failures seem to come in waves. If it fails the first time, it will also fail the 2nd, 3rd etc. Removing the modem does not help. But 1 or 2 hours later it might just work again. Alternatively if I want to repeat the problem, I can make 15 connections in a row without any failure. The other problem is that while the connection typically stays open for hours during normal web browsing, it will disconnect with quite high probability when downloading bigger files. Today I needed 4 attempts to download a 20 MB file. I would exclude network-side problems or weak signal, because I use 3G data on the same network nearly all day long on my smartphone without such problems. Additionlly, when the USB modem fails to connect I can use my phone as the modem using the data cable and everything works. So how could I debug this? Is it a Linux-side problem or a firmware problem in the CS-17? (Haven't had a chance to test it with M$ yet) >From searching in the mailing list archives I found 2 debugging hints: 1. starting nm from command line as # NM_SERIAL_DEBUG=1 NM_PPP_DEBUG=1 NetworkManager --no-daemon | tee log.txt That works nicely. When the connection attempt fails I see how PPP negotiation starts, but it doesn't seem to get any reply. sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x5c8b3860> <pcomp> <accomp>] After 5 repetitions pppd seems to give up and nm complains that the connection failed. (Not sure whether NM_SERIAL_DEBUG has any effect, I don't think I see that variable in the source code of my version) The problem is that using the command line (and root) is OK for me on my test machine, but not for the user in question on the real target machine. So I'd like to configure the "real" service such that logging is always on. I tried to do so by adding the 2 environment variables to /etc/init/network-manager.conf (Ubuntu uses upstart) env NM_PPP_DEBUG=1 env NM_SERIAL_DEBUG=1 exec NetworkManager Unfortunately that seems to have no effect to the pppd logging. The pppd stuff that I can see when running with --no-daemon does just not appear in syslog, neither in successful nor in failing cases. (I have checked from /proc/nnn/environ that the environment variables really end up in the network-manager process) Also the debug parameter appears on the pppd command line as shown in syslog. How can I get pppd logging when running as a daemon? 2. The other hint I found in the mailing archive was a config file entry [logging] level=WARN I changed that to level=DEBUG, but I don't think it made a difference. Could not find such parameter in my source code. Has it possibly been added only in a later version? Yesterday I read in some forum that killing modem-manager after a failed connection attempt helps. Today I had only very few failed attempts in my testing and killing modem-manager helped each time. Not yet sure whether this is really a reliable work-around. If yes, I could of course script it. Does the problem description ring any bells? If you remember specific fixes that solve these issues, I might try to backport them to my version. Or just install a newer version manually. Regards, Uwe P.S. Yes, I am aware of the modeswitching. I left that out from the description above, I'm sure that the modem was always in the right mode. _______________________________________________ networkmanager-list mailing list networkmanager-list@gnome.org http://mail.gnome.org/mailman/listinfo/networkmanager-list