Troubleshooting Tip: The firewall GUI is frequently disconnecting

seshuganesh · ‎08-16-2023

Description

This article describes troubleshooting steps to take when the firewall GUI frequently disconnects.

Scope

All versions of FortiOS.

Solution

Usually, this issue is caused by packet loss between the client (source machine) and FortiGate.

The first step is to connect the machine directly to the firewall and access the firewall. This should resolve most issues.

If the issue persists, execute the following command in the CLI:

diag sys top

See if any httpsd process got stuck in the D state. If any of the httpsd processes get stuck in the D state, it means that process could not contact the disk. In this case, it is necessary to reboot the firewall.

If there is no httpsd process in the D state, check the following debug output (an example is attached here):

diag debug crashlog read

Example output:

541: 2022-10-28 14:07:15 <00865> Backtrace:
542: 2022-10-28 14:07:15 <00865> [0x009c7cdc] => /bin/httpsd
543: 2022-10-28 14:07:15 <00865> [0x009c7fa0] => /bin/httpsd
544: 2022-10-28 14:07:15 <00865> [0x009c39e3] => /bin/httpsd
545: 2022-10-28 14:07:15 <00865> [0x00988edc] => /bin/httpsd
546: 2022-10-28 14:07:15 <00865> [0x00c3324a] => /bin/httpsd
547: 2022-10-28 14:07:15 <00865> [0x00c33806] => /bin/httpsd
548: 2022-10-28 14:07:15 <00865> [0x00c75f6b] => /bin/httpsd
549: 2022-10-28 14:07:15 <00865> [0x00c76141] => /bin/httpsd
550: 2022-10-28 14:07:15 <00865> [0x00c6ed3d] => /bin/httpsd
551: 2022-10-28 14:07:15 <00865> [0x00c3768a] => /bin/httpsd
552: 2022-10-28 14:07:15 <00865> [0x00c4c3aa] => /bin/httpsd
553: 2022-10-28 14:07:15 <00865> [0x00c4c696] => /bin/httpsd
554: 2022-10-28 14:07:15 <00865> [0x00c4cbf2] => /bin/httpsd
555: 2022-10-28 14:07:15 <00865> [0x00c48680] => /bin/httpsd
556: 2022-10-28 14:07:15 <00865> [0x00c481cf] => /bin/httpsd
557: 2022-10-28 14:07:15 <00865> [0x00435c20] => /bin/httpsd

If there is any output like the above, share this output to a TAC ticket.

If there is no crash, execute the following command and share the output to a TAC ticket:

diag debug reset

diag debug application httpsd -1

diag debug enable

After, access the firewall again. It should show some errors. Afterwards, disable the debugging:

diag debug disable