Switching

Hey guys, have two MX960's and two QFX5100's with mc-lag between the two, looking to configure jumbos between the two, when I look under the ae interfaces on the MX's I see mtu can be set to 9192, and the qfx can be set to 9216. Am I correct in saying they treat mtu sizes the same so I'll have set the QFX to 9192 to match MX's max size of 9192?

Yes. If you mean physical interface

QFX MTU range: 64 through 9216 bytes
MX MTU range: 256 through 9192 bytes
EX MTU range: 256 through 9216 bytes

Thanks, any idea why the difference is there?

Could you show interface configuration from both sides?

I think the cause in difference of hardware.

I've just checked out a few of my MX and EX and all of them have MTU limits - 9192 for MX and 9216 for EX. I think QFX has the same nature as EX.

Sure, I didnt see your last reply so sorry for the delay.

This is an MC-lag interface off the MX, several underlying units omitted to shorten it

ae0 {
    per-unit-scheduler;
    flexible-vlan-tagging;
    mtu 9192;
    encapsulation flexible-ethernet-services;
    aggregated-ether-options {
        lacp {
            active;
            periodic fast;
            system-id 00:00:00:00:00:01;
            admin-key 1;
        }
        mc-ae {
            mc-ae-id 1;
            redundancy-group 1;
            chassis-id 0;
            mode active-active;
            status-control active;
        }

QFX MC-lag to the MX again units/ vlans omitted to shorten:

ae0 {
    enable;
    mtu 9216;
    aggregated-ether-options {
        lacp {
            active;
            periodic fast;
            system-id 00:00:00:00:00:02;
            admin-key 1;
        }
        mc-ae {
            mc-ae-id 2;
            chassis-id 0;
            mode active-active;
            status-control active;
            init-delay-time 240;
        }
    }

Think better take this AS IS 🙂