diff --git a/src/freenas/etc/systemd/network/10-persistent-net.link b/src/freenas/etc/systemd/network/10-persistent-net.link index 1abd9b3ed366..d79f2554adcd 100644 --- a/src/freenas/etc/systemd/network/10-persistent-net.link +++ b/src/freenas/etc/systemd/network/10-persistent-net.link @@ -1,5 +1,15 @@ [Match] Driver=ntb_netdev + [Link] Name=ntb0 +# TODO: at time of writing, ntb on SCALE has pathological +# behavior related TCP/IP Window size calculation whereby +# the receiving side clamps the window size to 0 causing +# recalculation which, ultimately, ends with behavior +# described in https://en.wikipedia.org/wiki/Silly_window_syndrome +# The work-around is to drop MTU size a bit which fixes +# the scenario altogether. When we discover why this is +# happening, we should remove the MTUBytes line. +MTUBytes=64000