Cannot establish 10gig LAG between MX80 and EX4200 VC

[naveen@calpop.com]

Hi,

I am trying to connect an MX80 and EX4200 VC to establish a LAG channel. Currently only one 10gig link is used and will be later expanded to two.

The current configuration is as follows.

EX4200:

set chassis aggregated-devices ethernet device-count 64

set interfaces xe-0/1/0 ether-options 802.3ad ae0

set interfaces ae0 aggregated-ether-options minimum-links 1
set interfaces ae0 aggregated-ether-options lacp active
set interfaces ae0 aggregated-ether-options lacp periodic fast

MX80:

set chassis aggregated-devices ethernet device-count 64

set interfaces xe-0/0/1 gigether-options 802.3ad ae1

set interfaces ae1 vlan-tagging
set interfaces ae1 aggregated-ether-options minimum-links 1

set interfaces ae1 aggregated-ether-options lacp active
set interfaces ae1 aggregated-ether-options lacp periodic fast

When both ex4200:ae0 and mx80:ae1 do not have LACP configuration present, both interfaces show they're physically up. Every combination used for lacp active/passive doesn't seem to bring up the interfaces. I have not specified any logical units on the aggregated-ethernet interface nor the physical interface. I'm not sure if this is required.

Is there any other settings or conditions that are required so that LACP can operate and the interface will show as up.

Thanks.

[nikolay.semov]

I believe LACP requires matching MTU on both sides. Check the defaults, and, if necessary, explicitly configure MTU for the ae interfaces.

[ronf]

Are you sure that the lag is actually coming up when you do not have LACP configured? One of the things about LACP is that if frames are not really passing on the link, it will be marked down, whereas a static LAG will be up as long as the interfaces have physical link. Ron