vde qemu write: No buffer space available

[Mel Flynn]

On Friday 26 June 2009 10:04:13 Adam Vande More wrote:
> I'm having issues with high network throughput with vde and qemu.  There
> are two qemu vm's each running debian lenny and they are configured for
> drbd. The vm's work fine until drbd is started then the networking fails. 
> The only message I get(on the host side) is
>
> write: No buffer space available

It can be a driver issue, but the error message is somewhat misleading as it 
can be the result of an ill-configured firewall rule. Typically this happens 
when no state exists for the outgoing connection.

> which is echoed to console, and nothing appears in the logs.  I believe
> this to be an issue with vde, but I can't be certain because I can't seem
> to find any way to turn on more extensive logging.  Anyone have an idea how
> to resolve this?

You should check netstat -m to make sure there are mbufs available and if 
there is check your firewall. If all seems ok, try freebsd-net list for any 
known issues, since you didn't get any "me too's" here. You may want to 
specify a bit more info, like pciconf -lv for the vde device, vmstat -i at the 
time of the errors, ifconfig vde0 output and any firewall information 
(including "I don't have one" or "error persists if firewall is disabled").
-- 
Mel