Technical Tip: FortiGate-60E-DSL not connecting to DSL after upgrade

Solution

It is possible that after upgrading to FortiOS v7.4, the DSL connection remains down. This behavior can be related to the DSL modem firmware on the hardware model.

After rebooting the FortiGate unit, review the DSL debug output. Run the following commands and check for the specified message:

diagnose dsl show dsl-info
DSL module is not ready yet, please try again later.

diagnose debug application dsl -1

diagnose debug enable

adsl2plus_do_command[167]: create socket [6] ok

select write fd error [Operation now in progress]

adsl2plus_check_status[978]: n[-1]

R[0]V[0]L[0] S[0]U[0]

ADSL's link is down

When the debug output matches the example above, it is possible that a Special Technical Support (STS) firmware is required. In this case, open a support ticket with Fortinet Technical Support and include the outputs of the following commands:

get system status
show system interface dsl
diagnose hardware deviceinfo nic dsl

get system dsl status
diagnose dsl show 0
diagnose dsl show 1
diagnose dsl show 2

diagnose debug reset
diagnose debug disable
diagnose debug application dsl 255
diagnose debug application ppp 255
diagnose debug application pppoed 255
diagnose debug console timestamp enable
diagnose debug enable
execute interface pppoe-reconnect <interface>

Reproduce the DSL issue while the debug is running for at least one minute. Once it is complete, disable and reset the debugging:

diagnose debug disable

diagnose debug reset

Note: FortiOS v7.6 does not support FortiGate-60E-DSL or FortiWifi-60E-DSL.