Troubleshooting Tip: Frequent SNMP daemon crashes after upgrading to v7.6.4

After upgrading FortiGate from versions 7.4.x to 7.6.4, frequent SNMP daemon crashes may be found in the crashlog output 'diagnose debug crashlog read'.

This issue is caused by an error condition in the SNMP daemon that occurs when querying fgVpnSslStatsEntry after upgrading to version 7.6.4.

Example crash shown below: 

11841: 2025-08-31 12:35:30 <27468> firmware FortiGate-VM64 v7.6.4,build3596b3596,250820 (GA.F) (Release)
11842: 2025-08-31 12:35:30 <27468> application snmpd
11843: 2025-08-31 12:35:30 <27468> *** signal 31 (Bad system call) received ***
11844: 2025-08-31 12:35:30 <27468> Register dump:
11845: 2025-08-31 12:35:30 <27468> RAX: 000000000000001f RBX: 00007ffebed77c60
11846: 2025-08-31 12:35:30 <27468> RCX: 00007f0f5c0caa47 RDX: 00007ffebed77a60
11847: 2025-08-31 12:35:30 <27468> R08: 0000000000000000 R09: 00007f0f5c196be0
11848: 2025-08-31 12:35:30 <27468> R10: 0000000000000000 R11: 0000000000000246
11849: 2025-08-31 12:35:30 <27468> R12: 000000000007000e R13: 0000000000000000
11850: 2025-08-31 12:35:30 <27468> R14: 000055f305b2ada0 R15: 0000000000000001
11851: 2025-08-31 12:35:30 <27468> RSI: 0000000000000002 RDI: 000000000007000e
11852: 2025-08-31 12:35:30 <27468> RBP: 00007ffebed77af0 RSP: 00007ffebed77a58
11853: 2025-08-31 12:35:30 <27468> RIP: 00007f0f5c0caa47 EFLAGS: 0000000000000246
11854: 2025-08-31 12:35:30 <27468> CS: 0033 FS: 0000 GS: 0000
11855: 2025-08-31 12:35:30 <27468> Trap: 0000000000000000 Error: 0000000000000000
11856: 2025-08-31 12:35:30 <27468> OldMask: 0000000000000000
11857: 2025-08-31 12:35:30 <27468> CR2: 0000000000000000
11858: 2025-08-31 12:35:30 <27468> stack: 0x7ffebed77a58 - 0x7ffebed79010
11859: 2025-08-31 12:35:30 <27468> Backtrace:
11860: 2025-08-31 12:35:30 <27468> [0x7f0f5c0caa47] => /lib/libc.so.6 {0x7f0f5bfce000}
11861: 2025-08-31 12:35:30 <27468> [0x7f0f631301c7] => /lib/libncfg.so {0x7f0f630bd000}
11862: 2025-08-31 12:35:30 <27468> [0x7f0f631302f0] => /lib/libncfg.so {0x7f0f630bd000}
11863: 2025-08-31 12:35:30 <27468> [0x55f2fedad494] => /bin/snmpd {0x55f2faa3d000}
11864: 2025-08-31 12:35:30 <27468> [0x55f2fed50451] => /bin/snmpd {0x55f2faa3d000}
11865: 2025-08-31 12:35:30 <27468> [0x55f2fed4f7a9] => /bin/snmpd {0x55f2faa3d000}
11866: 2025-08-31 12:35:30 <27468> [0x55f2fed53a2b] => /bin/snmpd {0x55f2faa3d000}
11867: 2025-08-31 12:35:30 <27468> [0x55f2fed52b35] => /bin/snmpd {0x55f2faa3d000}
11868: 2025-08-31 12:35:30 <27468> [0x55f2fcbc314a] => /bin/snmpd {0x55f2faa3d000}
11869: 2025-08-31 12:35:30 <27468> [0x55f2fcbb8ff2] => /bin/snmpd {0x55f2faa3d000}
11870: 2025-08-31 12:35:30 <27468> [0x55f2fad90afc] => /bin/snmpd {0x55f2faa3d000}
11871: 2025-08-31 12:35:30 <27468> [0x55f2fad9f951] => /bin/snmpd {0x55f2faa3d000}
11872: 2025-08-31 12:35:30 <27468> [0x55f2fad9b385] => /bin/snmpd {0x55f2faa3d000}
11873: 2025-08-31 12:35:30 <27468> [0x55f2fad99698] => /bin/snmpd {0x55f2faa3d000}
11874: 2025-08-31 12:35:30 <27468> [0x7f0f5bff1e1b] => /lib/libc.so.6 {0x7f0f5bfce000}
11875: 2025-08-31 12:35:30 <27468> [0x55f2fad8fdaa] => /bin/snmpd {0x55f2faa3d000}
11876: 2025-08-31 12:35:30 <27468> fortidev 6.0.2.0008
11877: 2025-08-31 12:35:30 the killed daemon is /bin/snmpd: status=0x1f
11878: 2025-08-31 12:35:32 snmpd previously crashed 7 times. The last crash was at 2025-08-31 12:35:30.

The snmpd daemon may crash again after some time, even after restarting the daemon. Currently, there is no available workaround.

This issue has been resolved in:
v7.6.5 (available to download from the Fortinet Support portal).
v8.0.0 (scheduled to be released in April 2026).
These timelines for firmware release are estimated and may be subject to change.