NFS4 over tinc hangs

[Nikolaus Rath]

Guus Sliepen <guus-NnCthlHDAqpg9hUCZPvPmw at public.gmane.org> writes:
> On Sat, Mar 10, 2012 at 08:29:42PM -0500, Nikolaus Rath wrote:
>
>> The server has 4 relevant network interfaces:
>> 
>> eth0 - Internet
>> eth1 - Internal network
>> hbt  - Tinc VPN
>> vnet0 - Virtual hosts
>> br0 - Bridge between eth1 and vnet0
>> 
>> The hbt, br0 (i.e., eth1 and vnet0) interfaces share a common
>> 192.168.1.0/24 network. Proxy ARP is enabled for br0 and hbt.
>
> Just out of curiosity, why do you use proxy ARP in this case instead of adding
> hbt to the bridge? I assume you are you using Mode = switch?

No, I am using Mode = router. I used the switch configuration in the
past, but from the tinc docs I got the impression that proxy ARP +
router is the preferred option if I do not need to tunnel broadcast or
non-IP packets.

Are you saying that adding hbt to the bridge, disabling proxy ARP and
running with Mode = switch would be the better option for me? Then I'll
do that.


>> I am using tinc 1.0.16 on 3.0.0, 64bit Ubuntu 10.04 LTS on both server
>> and client.
>> 
>> The problem is that as soon as more than three tinc clients are
>> accessing the NFS shares, any operations on the NFS mountpoints by the
>> clients hang. On the clients, tinc then takes 100% CPU time. On the
>> server, the tinc stance runs with about 20% load. When activating tinc
>> debugging, tinc seems to be busy forwarding packets. I also ran a packet
>> sniffer which showed me that 90% of the packets were NFS related, but I
>> am not familiar enough with NFS to be able to tell anything from the
>> packets themselves.
>
> Can you show me a few lines of the debug messages when it is busy
> forwarding? Also, without full debugging enabled, when this happens,
> run "tincd -n <netname> -kUSR2" on one of the clients using 100% CPU
> and on the server, and send me the node, edge and subnet list that
> tinc logged. This allows me to see if there could be a routing loop
> within tinc or if there is another cause for this problem.
>
> Also please try out tinc 1.0.17 which has just been released, and
> check whether it also runs into the same problem.

Will do on Monday, thanks!


Best,

   -Nikolaus

-- 
 »Time flies like an arrow, fruit flies like a Banana.«

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