new gretap, bridging and mtu
Greetings all,
I've setup a new gretap device as per Herbert Xu's new patches and it works as expected for smaller MTU. I'm wondering if gretap tunnels handle fragmentation at all or if this might be a bridge related issue.
The same setup works quite well if I use vtun with a tap device however, so while this isn't entirely bridge-related, Maybe someone here might have experienced the same problem or might have insight as to what's causing the problem. I imagine this might be more of an inherent limitation in gretap than a bug but as I am not to good with coding, I figured I'd ask smarter people ;)
network1 box1 network2
box2 network1
801.2q (1504 bytes max) <-> (eth1-br0-gretap eth0) <-> (eth0 gretap-br0-eth1) <-> 801.2q (1504 bytes max)
Jonathan
Quoted 5 lines · Jonathan Thibault
network1 box1 network2 box2
network1
801.2q (1504 bytes max) <-> (eth1-br0-gretap eth0) <-> (eth0 gretap-br0-eth1) <-> 801.2q (1504 bytes max)
gretap should handle fragmentation in the same way as IP over GRE. The default for both is to disable fragmentation. You need to configure your tunnel to enable fragmentation by disabling PMTU if you want to use a larger MTU.
Cheers,
Signature · 4 lines
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