Description:
This article describes how to debug FortiExtender (FEX) interface shows disabled on FortiGate GUI as shown below:
User Impact: FortiGate may lose the Internet connection when FortiExtender (used as WAN uplink) interface shows disabled on the FortiGate GUI.
Debug (possible cause and fix):
1) Ensure FortiExtender is running on latest firmware in 4.2.x. or 7.x or 7.2.x
2) Verify if FortiExtender Interface gets disabled automatically or get disabled only after FortiGate reboot
3) If FortiExtender interface gets disabled after FortiGate reboot then on FortiGate verify if FortiExtender APN, SIM-PIN etc.
Settings are configured under Network -> FortiExtender -> Configure Settings as shown below:
# get system interface <----- To check FortiExtender default gateway IP.
# get modem status <----- To check FortiExtender modem status.
# execute shell5) After FortiExtender reboot and boot-up, does FortiExtender LTE connection work fine automatically or requires User intervention. If FortiExtender LTE does not work automatically then it requires FortiExtender LTE side troubleshooting (check references section).
# ping <IP_Address>
6) Ensure FortiExtender Ethernet port is not flapping due to physical layer issue with Ethernet Cable, PoE Switch or any Powering unit.
7) On FortiOS 6.4-2 – there was an issue reported (Bug 0653289) which is fixed in FortiOS 6.4-3.
Page#35.
8) Bug 0653289 workaround:
After FortiGate reboot, enable FortiExtender interface manually on FortiGate CLI as shown below:
edit "fext"
set vdom "root"
set mode dhcp
set status up <----- Change the status to ‘up’ if it is down.
set type fext-wan
set device-identification enable
set snmp-index 9
set macaddr f2:3e:94:xx:xx:xx
9) Restart FortiExtender daemon on FortiGate and check if that resolves the issue:
# execute extender restart-fortiextender-daemon
10) If this issue is frequently occurring then try FEX in the VLAN mode:
Related Articles
Technical Tip: How to configure and debug 4G LTE connection issues on FortiExtender (FEX)
