With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
dspuPuOperStartTime
Cisco DSPU Pu Operation Start Time
1.3.6.1.4.1.9.9.24.1.4.2.1.20
Timestamp of PU activation (when ACTPU +rsp received).
Back to CISCO-DSPU-MIB MIB page.
IPHost Network monitor allows you to monitor dspuPuOperStartTime on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.