Vlan interface limitations on J-series with ES
When attempting to configure a DHCP client on a vlan interface like this:
set interfaces vlan.100 family inet dhcp
A commit spawns an error that says I can only set up the DHCP client on a physical ethernet interface. Why does this even matter? A VLAN interface with family inet configured gets its own MAC address. Shouldn’t be a problem.
Also, it appears that if I set up a trunk between a J-series ES router and an EX switch, that any vlan.X interfaces with L3 addresses on the J-series are not available over the trunk from hosts on the switch. The only way to make it work is to assign the L3 address to a tagged logical unit on the physical interface. This is annoying. Can anyone else confirm this behavior?
I also read that link aggregation is not supported on the built in ports on the J-series. But it lets me configure it, and the link appears to be up. What is the real story on this? None of the Juniper engineers I spoke with knew much about it and were surprised that it even let me configure it. I have not tried sending traffic over it yet, but the ae0 interface is up/up on both ends.
9.4 lets me set the DHCP client on an L3 vlan interface now. Haven’t really tested the other two items.