On Mon, Jun 22, 2009 at 2:24 PM, Sven Eckelmannsven.eckelmann@gmx.de wrote:
On Monday 22 June 2009 21:57:07 Jacob Marble wrote: [...]
You can also set the mtu on your wifi devices higher (and bat0 devices). So for example wifi device to 1524 and bat0 to 1500 (like the eth devices). Also check if you have bridge mtu patch from Simon[1] (included in linux 2.6.27) when you are bridging some of the devices. Also check that icmp "Destination Unreachable" - "Fragmentation required, and DF flag set" isn't filtered anywhere.
[...]
The Linux workstations are attached via Ethernet, running Ubuntu.
The MTU, by default, is 1500 on eth0, ath0, wifi0 The MTU, by default, is 1476 on bat0, br-lan
Ping from Linux workstation to Linux workstation works as long as the -s flag is 1448 or less. 1448 = 1476 - 28 The -M do doesn't seem to change anything.
HTTP transfers still don't go through when they are larger than ~1400 bytes. I'll go play with the MTUs now.
Ok, setting mtu of ath0's to 1524 and of bat0 to 1500 should help here. Just for the sake of completeness: Is there bridging involved in the workstations or any icmp filtering on the workstations/nanostations?
Regards, Sven
Yes. However, I can't set the MTU any higher than 1476 on the bat0 interface:
root@OpenWrt:~# ifconfig bat0 mtu 1500 ifconfig: SIOCSIFMTU: Invalid argument root@OpenWrt:~# ifconfig bat0 mtu 1477 ifconfig: SIOCSIFMTU: Invalid argument root@OpenWrt:~# ifconfig bat0 mtu 1476 root@OpenWrt:~#
The same thing goes for the br-lan interface, I assume because brctl uses the lowest MTU of all bridged interfaces as its max MTU.