On Fri, 12 Jan 2018 09:34:13 +0100, Jiri Benc wrote: > I don't think this works currently. When someone (does not have to be > you, it can be a management software running in background) sets the > MTU to the current value, the magic behavior is lost without any way to > restore it (unless I'm missing a way to restore it, see my question > above). So any user that depends on the magic behavior is broken anyway > even now.
Upon further inspection, it seems that currently, slaves always follow master's MTU without a way to change it. Tough situation. Even implementing user space toggleable mtu_adj could break users in the way I described. But it seems to be the lesser evil, at least there would be a way to unbreak the scripts with one line addition. But it's absolute must to have this visible to the user space and changeable. Something like this: # ip a 123: ipvlan0: <FLAGS> mtu 1500 (auto) qdisc ... # ip l s ipvlan0 mtu 1400 # ip a 123: ipvlan0: <FLAGS> mtu 1400 qdisc ... # ip l s ipvlan0 mtu auto # ip a 123: ipvlan0: <FLAGS> mtu 1500 (auto) qdisc ... Jiri
