Here is a quick way that you can add a cron job in ESXi 5.x. You will notice that there are already jobs in here that run on a schedule by default, the last line is new.
Edit the below file:
The last line in the below file will run at 12:01AM UTC time and will delete any file that ends with .trp in the /var/spool/snmp folder.
Contents of the “root” file:
#min hour day mon dow command
1 1 * * * /sbin/tmpwatch.py
1 * * * * /sbin/auto-backup.sh
0 * * * * /usr/lib/vmware/vmksummary/log-heartbeat.py
*/5 * * * * /sbin/hostd-probe
1 0 * * * for i in /var/spool/snmp/*.trp; do rm -rf $i; done