Linking a fs.com with a Juniper switch using 802.3ad with LACP was not as straightforward as intended. While you can configure aggregated ports using the switch web interface, it won’t let you set the correct modes for LACP.

The fs.com documentation is quite horrible, and I will spare you the time to read it.

Connect to your switch using ssh, go into configuration mode and wipe any existing configuration for your desired LACP ports, either by ‘default interface <interfacename>’ or by removing any configuration line by line.

I decided to bundle GigabitEthernet 0/11 and Gigabitethernet 0/12 to an aggregation interface:

interface GigabitEthernet 0/11
  port-group 1 mode active
  lacp port-priority 1

interface GigabitEthernet 0/12
  port-group 1 mode active
  lacp port-priority 1

interface AggregatePort 1
  description LACP Link to jswitch
  mtu 1514

And surprisingly, that did work:

FS#sh lacp summary

System Id:32768, 649d.99d0.5c28

Flags:  S - Device is requesting Slow LACPDUs   F - Device is requesting Fast LACPDUs.
A - Device is in active mode.        P - Device is in passive mode.

Aggregate port 1:

Local information:
                                     LACP port       Oper    Port    Port
Port           Flags     State       Priority        Key     Number  State
---------------------------------------------------------------------------
Gi0/11         SA        bndl        1               0x1     0xb     0x3d
Gi0/12         SA        bndl        1               0x1     0xc     0x3d

The Juniper end seems happy with it too.

Aggregated interface: ae0
    LACP state:       Role   Exp   Def  Dist  Col  Syn  Aggr  Timeout  Activity
      ge-0/1/0       Actor    No    No   Yes  Yes  Yes   Yes     Fast    Active
      ge-0/1/0     Partner    No    No   Yes  Yes  Yes   Yes     Slow    Active
      ge-0/1/1       Actor    No    No   Yes  Yes  Yes   Yes     Fast    Active
      ge-0/1/1     Partner    No    No   Yes  Yes  Yes   Yes     Slow    Active
    LACP protocol:        Receive State  Transmit State          Mux State
      ge-0/1/0                  Current   Slow periodic Collecting distributing
      ge-0/1/1                  Current   Slow periodic Collecting distributing