With IPHost Network Monitor you can run simple snmp requests against a HP device in your network.
error21-time-stamp
error21-time-stamp
1.3.6.1.4.1.11.2.3.9.4.2.1.1.11.21.1
Contains some sort of time stamp indicating when error 21 occurred. Example time stamps include the actual time the error occurred (in seconds since Jan. 1, 1970), and the total engine page count. The device POS documents the meaning of the time stamp. Additional information: See ERROR1-TIME-STAMP.
Back to hpclj4500 MIB page.
IPHost Network monitor allows you to monitor error21-time-stamp on Hewlett Packard device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco optical switches right now.