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mlaverdiere 07-27-2004 09:04 AM

Intermittent Internet connection drops
Hi to all,

Here's my story:

I'm running Debian Sid (Unstable), with a custom 2.6.5 Kernel on a Sony Vaio Laptop PCG-K13Q. I connect to Internet through a wireless Netgear routeur using either the integrated Atheros wifi card or my PCMCIA Netgear MA401 wireless card. I prefer to use the Netgear card because it gives me a far stronger signal everywhere in the house.

The problem is that I experience some intermittent Internet connection drops or big slowdowns with the Netgear card. It may be when I start the computer or at any time when I'm browsing on the Net. My wife, who also have a Netgear card on his Windoze Me laptop, doesn't have this problem, so I guess that this is not a ISP/router problem. When the problem occurs, I can still access the wireless router internal html configuration wizard without problems. So this does not seem to be a problem with the wireless connection between the laptop and the router.

After some search, I thought that it could be a MTU related problem, so I tried various MTU settings, without success... I now suspect that it may be a DHCP or a DNS related problem, but I don't know how to handle this...

Someone has an idea of what could be the problem?

Thanks for your help.
Here's the content of my /etc/pcmcia/network.opts file, by which the connection with the Netgear card is configured:

# Network adapter configuration
# The address format is "scheme,socket,instance,hwaddr".
# Note: the "network address" here is NOT the same as the IP address.
# See the Networking HOWTO. In short, the network address is the IP
# address masked by the netmask.
case "$ADDRESS" in
INFO="Sample private network setup"
# Transceiver selection, for some cards -- see 'man ifport'
# Use BOOTP (via /sbin/bootpc, or /sbin/pump)? [y/n]
# Use DHCP (via /sbin/dhcpcd, /sbin/dhclient, or /sbin/pump)? [y/n]
# If you need to explicitly specify a hostname for DHCP requests
# Use PPP over Ethernet (via the pppoe package)? [y/n]
# Use WHEREAMI (via the whereami package)? [y/n]
# Host's IP address, netmask, network address, broadcast address
# Gateway address for static routing
# Things to add to /etc/resolv.conf for this interface
# The nameserver IP addresses specified here complement the
# nameservers already defined in /etc/resolv.conf. These nameservers
# will be added to /etc/resolv.conf automatically when the PCMCIA
# network connection is established and removed from this file when
# the connection is broken.
# NFS mounts, should be listed in /etc/fstab
# If you need to override the interface's MTU...
# For IPX interfaces, the frame type and network number
# Run ipmasq? [y/n] (see the Debian ipmasq package)
# Extra stuff to do after setting up the interface
start_fn () { return; }
# Extra stuff to do before shutting down the interface
stop_fn () { return; }
# Card eject policy options

# This tries to use Debian's network setup in /etc/network/interfaces
# if no settings are given higher up in this file. You can delete it
# if that isn't desired.
#is_true $DHCLIENT || \
#is_true $PUMP || is_true $BOOTP || is_true $DHCP || \
#[ -x /proc/sys/kernel/hotplug ] || \
#if [ -z "$IPADDR" -a -f /etc/network/interfaces ] ; then
# INFO="Debian network setup"
# start_fn () {
# log /sbin/ifup $1
# }
# stop_fn () {
# log /sbin/ifdown $1
# }

mlaverdiere 07-30-2004 08:16 AM

Well, it seems that there is something happening with the "Tx packets". Here's the output of "ifconfig eth2" when the connection is in the intermittent slowdown mode describe in my previous post :

ifconfig eth2
eth2 Lien encap:Ethernet HWaddr 00:09:5B:25:F4:B5
inet adr: Bcast: Masque:25
adr inet6: fe80::209:5bff:fe25:f4b5/64 Scope:Lien
RX packets:5348 errors:0 dropped:0 overruns:0 frame: 0
TX packets:5485 errors:2 dropped:0 overruns:0 carrie r:0
collisions:0 lg file transmission:1000
RX bytes:3890601 (3.7 MiB) TX bytes:1112274 (1.0 Mi B)
Interruption:3 Adresse de base:0x100

What's the meaning of "... TX packets:5485 errors:2..."? Any idea someone?


mlaverdiere 08-21-2004 06:23 PM

Ok, after a long fight, here's what I found: the problem was with my Netgear MR814 router. The solution: downgrade (yes, you read downgrade!) the firmware from 4.14 RC4 to 4.13 version.

Everything's working fine since 2 weeks now.

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