Wireless service stops suddenly

bogzab · 05-04-2007, 11:11 AM

I have a Slackware box configured as a home server on a wireless link to my DSL / router which talks to my main workstation (Suse 10.2 currently) via an ethernet cable and to other devices around the house by wireless links. I have configured FTP, NFS and Samba services on the server.

When the server is doing low volume work (browsing on the DSL, small file transfers to and from other PCs) there is no problem. But if I do a sustained transfer of a big directory of MP3s, for example, then the server - router link will simply give up at some point (today once after 170MB transferred, then again after 280MB). Restarting the wireless access point on the router or restarting the server always cures the problem.

My question is : can anyone tell me what logs are available to help me to understand what is failing and why. All protools (ftp, samba, nfs) seem to suffer the same problem so I assume the problem is deeper in the wireless connectivity. Only HTTP does not seem to suffer but I guess this traffic is never as high in volume.

Any help appreciated.

onebuck · 05-04-2007, 11:33 AM

Quote:

Originally Posted by bogzab

I have a Slackware box configured as a home server on a wireless link to my DSL / router which talks to my main workstation (Suse 10.2 currently) via an ethernet cable and to other devices around the house by wireless links. I have configured FTP, NFS and Samba services on the server.

When the server is doing low volume work (browsing on the DSL, small file transfers to and from other PCs) there is no problem. But if I do a sustained transfer of a big directory of MP3s, for example, then the server - router link will simply give up at some point (today once after 170MB transferred, then again after 280MB). Restarting the wireless access point on the router or restarting the server always cures the problem.

My question is : can anyone tell me what logs are available to help me to understand what is failing and why. All protools (ftp, samba, nfs) seem to suffer the same problem so I assume the problem is deeper in the wireless connectivity. Only HTTP does not seem to suffer but I guess this traffic is never as high in volume.

Any help appreciated.

Hi,

The logs are in /var/log;

Code:

amos:~# ls /var/log
Xorg.1.log  debug    maillog.1   packages/          setup/     syslog.3
apache/     debug.1  maillog.2   removed_packages/  spooler    syslog.4
apache2/    debug.2  maillog.3   removed_scripts/   spooler.1  uucp/
btmp        debug.3  maillog.4   samba/             spooler.2  wtmp
cron        debug.4  messages    scripts/           spooler.3  wtmp.1
cron.1      dmesg    messages.1  secure             spooler.4
cron.2      faillog  messages.2  secure.1           squid/
cron.3      iptraf/  messages.3  secure.2           syslog
cron.4      lastlog  messages.4  secure.3           syslog.1
cups/       maillog  nfsd/       secure.4           syslog.2

The above is sample for one of my servers.

You should be looking at the '/var/log/syslog', 'var/log/debug' (if you have debug on) or '/var/log/dmesg'. I can't be specific since I don't know how you have your system configured.

You should see any relative errors in the 'dmesg' or 'syslog'.

If you show a listing of the '/var/log' then we could wag (wild ass guess' it. Then request the post of a particular log.

EDIT: PS; You should make sure the lease time is sufficient for the AP. Also possible limits on the AP for the IP.

bogzab · 05-06-2007, 01:03 PM

Quote:

Originally Posted by onebuck

Hi,

The logs are in /var/log;

Code:

amos:~# ls /var/log
Xorg.1.log  debug    maillog.1   packages/          setup/     syslog.3
apache/     debug.1  maillog.2   removed_packages/  spooler    syslog.4
apache2/    debug.2  maillog.3   removed_scripts/   spooler.1  uucp/
btmp        debug.3  maillog.4   samba/             spooler.2  wtmp
cron        debug.4  messages    scripts/           spooler.3  wtmp.1
cron.1      dmesg    messages.1  secure             spooler.4
cron.2      faillog  messages.2  secure.1           squid/
cron.3      iptraf/  messages.3  secure.2           syslog
cron.4      lastlog  messages.4  secure.3           syslog.1
cups/       maillog  nfsd/       secure.4           syslog.2

The above is sample for one of my servers.

You should be looking at the '/var/log/syslog', 'var/log/debug' (if you have debug on) or '/var/log/dmesg'. I can't be specific since I don't know how you have your system configured.

You should see any relative errors in the 'dmesg' or 'syslog'.

If you show a listing of the '/var/log' then we could wag (wild ass guess' it. Then request the post of a particular log.

EDIT: PS; You should make sure the lease time is sufficient for the AP. Also possible limits on the AP for the IP.

Thanks for these helpful hints. My /var/log looks like this:

Code:

Xorg.0.log      cron.4     maillog.2             samba/             secure.1   syslog.4
Xorg.0.log.old  cups/      maillog.3             samba.0.0.0.0      secure.2   uucp/
Xorg.1.log      debug      maillog.4             samba.192.168.1.2  secure.3   vsftpd.log
Xorg.1.log.old  debug.1    messages              samba.192.168.1.3  secure.4   vsftpd.log.1
Xorg.2.log      debug.2    messages.1            samba.192.168.1.4  setup/     vsftpd.log.2
Xorg.3.log      debug.3    messages.2            samba.192.168.1.5  spooler    vsftpd.log.3
acpid           debug.4    messages.3            samba.192.168.1.6  spooler.1  vsftpd.log.4
apache/         dmesg      messages.4            samba.linux-tigby  spooler.2  wtmp
btmp            faillog    nfsd/                 samba.nmbd         spooler.3  wtmp.1
btmp.1          iptraf/    nvidia-installer.log  samba.sassinder    spooler.4
cron            kdm.log    packages/             samba.smbd         syslog
cron.1          lastlog    removed_packages/     samba.tigby-serv   syslog.1
cron.2          maillog    removed_scripts/      scripts/           syslog.2
cron.3          maillog.1  sa/                   secure             syslog.3

I have had a look in dmesg and syslog and there seems nothing very obvious regarding the wifi interface going down. syslog has messages regarding booting up the wifi interface. I have upgraded to the latest madwifi drivers from source and this seems to have improved matters a little, but the wifi link still seems to go down at random times and expecially if used intensively. I have checked the lease time and increased it form one hour to six hours. Was not sure what you meant by limits on the "AP for the IP"? If I cannot get any clues from the logs then I was going to try to install kernel 2.6 rather than 2.4, which I opted for when I first installed Slackware 11. I was somewhere that 2.6 was better for wifi connectivity - is thie correct?

Thanks

pappy_mcfae · 05-07-2007, 01:17 AM

Quote:

Originally Posted by bogzab

....I was somewhere that 2.6 was better for wifi connectivity - is thie correct?

Thanks

My experience is I couldn't even get my wireless adapter to run under 2.4 kernel. Once I compiled my own 2.6 kernel, not only did my wireless network begin to operate, so did my USB mouse, and my flash player became able to play sound as well as video when I went to Youtube.

I recommend compiling a custom kernel of your own, not using one of the pre-compiled ones that come with Slackware. You will need to compile file system support directly into the kernel. The generic 2.6 kernels that come with the Slackware distribution rely on modules to load the file system. Can you say kernel panic?

Sure, I knew you could!

Hope that helps.

Blessed be!
Pappy

dunric · 05-07-2007, 04:45 AM

Sometimes it's a hardware problem with wireless device - it's not so uncommon behaviour at lower-end models when wifi device is 'choked' by high loads or too much open connections.
I would first try to exchange with other AP model if you have the possibility.

onebuck · 05-08-2007, 08:42 AM

Hi,

Another possible problem would be channel conflict. Other wireless devices in proximity of your AP causing conflicts. You could do a scan to see if a neighbor is using the same channel. Some wireless phones have caused problems with certain APs' with overlap.

unixfool · 05-08-2007, 09:30 AM

Quote:

Originally Posted by onebuck

Hi,

Another possible problem would be channel conflict. Other wireless devices in proximity of your AP causing conflicts. You could do a scan to see if a neighbor is using the same channel. Some wireless phones have caused problems with certain APs' with overlap.

Cell phones and microwave ovens also use the same band as APs and wireless cards.