Just though I'd check with the networking gurus out there. 802.3ad doesn't seem to actually failover if the speed of the links are different. I noticed I could ping out from the server but couldn't ping the server itself from another system but this could just be the result of the way our networking guys have things set up. I can't seem to find any documentation specifically saying that it's not fault tolerant but I did notice that the kernel documentation for channel bonding specifies that certain link aggregation modes were fault tolerant and didn't specify it for 802.3ad or mode 4. Is this mode not meant to be fault tolerant?

The 802.3ad link aggregation require both side in 802.3ad mode. Is peer equipment configured as 802.3ad link aggregation?

To the best of my knowledge you must have the same speed links to create an lacp bundle. Can't remember if the spec states this but its certianly a limitation on any kit I've worked on. Chances are you configured them as lacp but they weren't actively bundled, remember LACP negitiates bundle members. Just because you configured an interface in a bundle doesn't mean its actually there.

LACP is fault tolerant if set up right. All communications should function normally as long as any one member of the bundle is up.