Mongo DB crashes after a few days. Im not sure why

[chris-martin@community.nodebb.org]

mongod and noddbb logs below

systemctl status mongod

× mongod.service - MongoDB Database Server
     Loaded: loaded (/usr/lib/systemd/system/mongod.service; enabled; preset: enabled)
     Active: failed (Result: core-dump) since Fri 2026-01-23 11:19:04 GMT; 1 day 10h ago
   Duration: 4d 19h 14min 43.486s
       Docs: https://docs.mongodb.org/manual
    Process: 652376 ExecStart=/usr/bin/mongod --config /etc/mongod.conf (code=dumped, signal=ABRT)
   Main PID: 652376 (code=dumped, signal=ABRT)
        CPU: 1h 59min 50.180s

Jan 18 16:04:20 c-lap systemd[1]: Started mongod.service - MongoDB Database Server.
Jan 18 16:04:21 c-lap mongod[652376]: {"t":{"$date":"2026-01-18T16:04:21.000Z"},"s":"I",  "c":"CONTROL",  "id":7484500, "ctx":"main","msg":"Environment variable MONGODB_CONFIG_OVERRIDE_NOFORK == 1, overriding>
Jan 23 11:19:04 c-lap systemd[1]: mongod.service: Main process exited, code=dumped, status=6/ABRT
Jan 23 11:19:04 c-lap systemd[1]: mongod.service: Failed with result 'core-dump'.
Jan 23 11:19:04 c-lap systemd[1]: mongod.service: Consumed 1h 59min 50.180s CPU time, 526.6M memory peak, 0B memory swap peak.

NodeBB log

mongod.log

[baris@community.nodebb.org]

Does it happen if you disable diagnostic data collection?

setParameter:
   diagnosticDataCollectionEnabled: false

Your mongod.log shows mongodb crashed while trying to collect diagnostic data.

{"t":{
"$date":"2026-01-23T11:18:45.343+00:00"},"s":"F",  "c":"FTDC",     "id":9399800, "ctx":"ftdc",
"msg":"Exception thrown in full-time diagnostic data capture subsystem. Terminating the process because diagnostics cannot be captured.",
"attr":{"exception":{
"code":13548,"codeName":"Location13548",
"errmsg":"BufBuilder attempted to grow() to 131072741 bytes, past the 125MB limit."}}}