[ovs-discuss] multicast problems with OVSIntPort

Dietmar Maurer dietmar at proxmox.com
Fri May 9 08:40:04 UTC 2014


> > In either case, just the
> > "multicast" traffic should not have any negative effect.
> 
> tcpdump reveals that corosync packets have wrong cksum:
> 
> # tcpdump -envv "port 5404" -i test1
> 07:50:59.927572 be:94:dc:b2:f8:8c > 01:00:5e:40:a6:1e, ethertype IPv4
> (0x0800), length 161: (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17),
> length 147)
>     10.11.12.1.5404 > 239.192.166.30.5405: [bad udp cksum 0xac7b -> 0x36e2!]
> UDP, length 119

I just noticed that I get bad checksum also with 'config1', so that cannot be the reason.
Any idea why we get bad checksum - is that normal?

> The nodes are directly connected using a crossover cable, so there is no
> switch involved.

The bug somehow depends on kernel and network card/driver, for example
using igb 5.1.2 work with kernel 3.10, but fails with kernel 2.6.32:

/lib/modules/2.6.32-29-pve/kernel/drivers/net/igb/igb.ko ==> fails
/lib/modules/3.10.0-2-pve/kernel/drivers/net/ethernet/intel/igb/igb.ko ==> works

The bug always triggers when I use Broadcom Tigon3 tg3.ko 3.132.

So 'config1' works always, and 'config2' depends on kernel/driver.

And idea how to debug that?

 


More information about the discuss mailing list