Layer 2 LACP bonding

What code are you running? I believe vPC support on extenders have been available in  the latest NX-OS  for a host and same extender,  but I think you need to look at the NX-OS extender type and switch-type  that's uses for across extenders. This would be a enhanced vPC configuration for server and data centers.You should really ask this in  the cisco forum since the support and requires are a cisco requirement.

But I would check the  switch and fex type and NXOS, but etherbundle across  extenders are doable.

btw; i believe the 35xx don't support this,  and you will need to be on hardware of a 7k or 5k series

cisco Nexus 5596

version 6.0(2)N1(2a)

Okay so what do you have configured at the host level? And do you have any lacp  pcap captures?

Also did you try the " no lacp suspend-individual "  command  on the member ports? You can also monitor the lacp counters for control packets between host and FEX and/or debug lacp error

(e.g)

"show lacp counters interface port-channel xxxx"

NOTE: It might be in that NX-OS software code and switch,  but it's doesn't exist in a 3548 so I can't confirm for your model.

nexus32-RD5# show lacp counters interface port-channel 6                     LACPDUs         Marker      Marker Response    LACPDUs Port              Sent   Recv     Sent   Recv     Sent   Recv      Pkts Err --------------------------------------------------------------------- port-channel6 Ethernet102/1/35   209    0        0      0        0      0        0 Ethernet103/1/35   208    0        0      0        0      0        0   well I think that the problem is with fortigate, since I am not receiving any LACP PDUs I don't know how to configure port channel on fortigate properly...

solved

reboot of the FGT was the solution