vme.0 up/down on new QFX5100 VC pair

I'm installing a new set of QFX5100s and am having difficulty with the vme management interface. I have two QFX5100s in a VC pair, and have C0 (em0) on each QFX5100 connected to our management network. Very minimal config on the QFXs, and we're at least initially not doing any layer-3 on them.

admin@dcas01a-ts1dc> show interfaces terse vme     
Interface               Admin Link Proto    Local                 Remote
vme                     up    down
vme.0                   up    down inet     10.38.4.87/24    

{master:0}
admin@dcas01a-ts1dc> show interfaces terse em0  
Interface               Admin Link Proto    Local                 Remote
em0                     up    up
em0.0                   up    up   

{master:0}