Purpose
Purging may not have been set up at installation time. If the OMK database has grown large it's a good idea to purge it in 90 day increments until the desired retention period is realized.
Determine the Purge Older Than Value
In order to purge from the database in 90 day increments the date of the oldest record is required.
[root@opmantek ~]# mongo -u opUserRW -p op42flow42 nmis --eval 'db.rawlogs.findOne()'
MongoDB shell version v3.4.9
connecting to: mongodb://127.0.0.1:27017/nmis
MongoDB server version: 3.4.9
{
"_id" : ObjectId("5543df5db5d690352f1eb2cb"),
"entry" : "2015-05-01T16:17:19\t10.73.225.166\tUDP: [10.73.225.166]:14445->[10.72.0.31]\tSNMPv2-MIB::sysUpTime.0=23:5:15:52.26\tSNMPv2-MIB::snmpTrapOID.0=SNMPv2-SMI::enterprises.8072.4.0.3\tSNMPv2-MIB::snmpTrapEnterprise.0=SNMPv2-SMI::enterprises.8072.4",
"time" : NumberLong(1430511439),
"eventid" : ObjectId("5543df5db5d690352f1eb2ca"),
"type" : "nmis_traplog"
}
Notice the 'time' property above; 1430511439. The date command may be used to reveal when this was.
[root@opmantek ~]# date --date @1430511439 Fri May 1 20:17:19 UTC 2015
The purge command can be passed a value in minutes with the option 'events_purge_older_than'.
### Current unix epoch time [root@opmantek ~]# date +%s 1513316674 ### Let X be The difference of current time and oldest record time converted to minutes >>> (1513316674-1430511439)/60 1380087.25 ### There are 129600 minutes in 90 days. Subtract 129600 minutes from X. >>> 1380087 - 129600 1250487 ### Based on this the events_purge_older_than should be 1250487