Has anyone had success adjusting MTU on OpenVPN tunnel adapters to deal
with loss amplification across tunnel networks?
By default the MTU on an openVPN adapter(s) are set to 1500, but it
seems that performance in lossy conditions might be dramatically
improved by changing the MTU to something smaller to prevent packet
fragmentation across the tunnel network (e.g. to account for the
encrypted packet's IP overhead, such that one packet could be
encapsulated by one packet of the tunnel network). It seems that if the
MTU's are the same, one would invariably end up with frequent
fragmentation, greatly increasing the packet loss amplification on lossy
(e.g. wireless) networks, and exaggerated falloff of application
performance as packet loss increases. This is also consistent with what
I observe.
I understand that this artificial constraint would result in lower
performance in high quality connections, but am I on the right track to
dealing with performance on lossy networks? If this is conceptually
correct, so would I also need to explicitly tell OpenVPN not to fragment
in general? Any big-picture guidance would be much appreciated.
_______________________________________________
pfSense mailing list
https://lists.pfsense.org/mailman/listinfo/list
Support the project with Gold! https://pfsense.org/gold
