Last week, I tried to gang 2 10GE interfaces on a Sun X4540 "Thor" to an HP ProCurve 2900. We had Sun's dual 10GE fiber XFP adapter & SR-XFP transceivers, and a couple ProCurve SR transceivers. nxge0 & nxge1 were both okay, but LACP link aggregation didn't work.

Each time I set up the Sun aggregate with dladm create-aggr, things looked okay. But when I enabled aggregation on the ProCurve ports with int a1,a4 lacp active, nxge1 lost its link. I spoke to a couple Sun reps, who agreed this should work and sounded like an unknown bug.

Fortunately, we discovered that adding -l active to the dladm command worked. LACP should work with one partner active and the other passive, or with both active. In our case it fails with active/passive, but works active/active.