We're eventually looking to get jumbo frames working between our
225s/275s and the controllers, once we manage to plumb jumbo
across the distro/edge.
As far as I can see by the manual, this is specific to AP communications
tunnels, and would not affect the MTU used by other services on the
controller, e.g. ssh, web, Airwave communications, RADIUS, syslog. Is this
a correct assessment? Or if not, is the controller going to properly
PMTUD all these services?
The manual seems to infer that all that is needed is one firewall
setting, and then to set the MTU on port channels/interfaces on the
controller. When we initially installed the controller we turned all these
bells on, even though we knew the distro layer would swat down
the traffic, and PMTUD seems to have done the trick and kept everything
more or less happy since then, minus of course the HP switches whining
about the DF probe packets..
We do note, however, that even though jumbo is enabled on both
the controller 10G uplinks, and the portchannel to which they belong,
a show interfaces command will show the portchannel at 9216 but the
member ports still have MTU 1500 showing (and do not show the
Jumbo support status line). We also wonder whether the MTU setting on
the SVI for the vlan serving AP tunnels will need attention.
Interested to hear if anyone has got this working and whether there
were any additional pitfalls or things to look out for.
#AP225