[solved] problems with timeouts and tcp retransmission

equilibrium · 2009-11-30 21:43:19

I've recently upgraded my archlinux and am having real problems with the network.

I have checked the configuation and all seems ok.
Everything like DNS/Gateways/IPs all seem to be setup (not changed anything from when it was working before)

I read about setting the MTU manually

ifconfig eth0 mtu 1492

I tried this but it doesn't seem to make any difference

Looking at the packetflow on wireshark it seems that there are a huge amount of TCP Dup ACK and TCP Retransmission when trying to POST

If I boot into windows everything is fine so unfortunately it seems that it might be something with linux

Everything in linux seemed to be working ok before I upgraded

Last edited by equilibrium (2009-12-05 15:13:14)

equilibrium · 2009-12-03 18:28:25

seems that I am still unable to post from my arch system

$ dmesg | grep sky2
sky2 driver version 1.23
sky2 0000:02:00.0: PCI INT A -> GSI 19 (level, low) -> IRQ 19
sky2 0000:02:00.0: setting latency timer to 64
sky2 0000:02:00.0: Yukon-2 EC chip revision 2
sky2 0000:02:00.0: irq 29 for MSI/MSI-X
sky2 eth0: addr xx:xx:xx:xx:xx:xx
sky2 eth0: enabling interface
sky2 eth0: Link is up at 100 Mbps, full duplex, flow control both

$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:17:31:F4:ED:A2  
          inet addr:192.168.1.20  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1170 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1362 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1101154 (1.0 Mb)  TX bytes:197742 (193.1 Kb)
          Interrupt:19 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:4595 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4595 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:541498 (528.8 Kb)  TX bytes:541498 (528.8 Kb)

/etc/rc.conf

eth0="eth0 192.168.1.20 netmask 255.255.255.0 broadcast 192.168.1.255"
INTERFACES=(eth0)
gateway="default gw 192.168.1.1"
ROUTES=(gateway)

equilibrium · 2009-12-04 22:16:07

Not sure if this is a problem with the NIC

Just tried a few things.
With another NIC I get the same.
With the newest kernel I get the same.
With another distro (livecd) I get the same.
I upgraded the router firmware - still the same
Reset router settings to default and re-setup - still the same

I thought it might be the MTU setting as it only seems to not work when transmitting/posting a lot of information.

My router is a WRT54GS and I'm running tomato firmware on it (not sure if there are any known issues?)
I might try putting DD-WRT onto it just to try but other than that I'm not sure what else it could be?

equilibrium · 2009-12-05 15:15:28

Finally got it fixed now

Put on DD-WRT reset everything to defaults and re-setup the firewall/dhcp/vpn/dns/qos/voip/nat etc and it seems to work ok now.
Not sure what happened with tomato but nvm as it's working now

Arch Linux

#1 2009-11-30 21:43:19

[solved] problems with timeouts and tcp retransmission

#2 2009-12-03 18:28:25

Re: [solved] problems with timeouts and tcp retransmission

#3 2009-12-04 22:16:07

Re: [solved] problems with timeouts and tcp retransmission

#4 2009-12-05 15:15:28

Re: [solved] problems with timeouts and tcp retransmission

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