HP AA HP Netserver 4000 Reference Guide

Ch 6: Backp and Restore
Network Server Division
6-11
Disaster recovery procedures
In the event of a disaster or an operator's error, it is possible that the
CE OS can be put in an inoperable state. When this occurs it may be
possible to recover the system without restoring from backup tapes.
Below is a set of procedures to assist system administrators to
recover systems with minimum downtime. The procedures must be
followed in order listed below.
1. Last Known Good (Control Set)
Some failures of a CE OS to boot (after a reconfiguration) can be
recovered from by selecting the “Last Known Good”
configuration. This functionality is exactly the same as the
reference machine (standard NT) case where you strike the space
bar on the keyboard when prompted – and prior to the first log
on following the configuration change. Follow the steps below:
a. Boot both IOPs in Marathon Operation Mode and observe if
both CE NOS disks are up-to-date (i.e., both should be green
on the Marathon Management GUI). If so, select one of the
two tuples as the "booting tuple." If only one of them is up-
to-date, select the tuple containing the the up-to-date NOS
disk as the "booting tuple."
b. Set the monitor/keyboard switch to enable keyboard on the
"booting tuple" side.
c. Set the monitor switch on SSDL of the "booting tuple" to
CE.
d. Power on only the CE in the "booting tuple".
e. System will initialize itself. When you receive the message
on the CE "Initiating Marathon Boot", followed by MIC
BIOS: CE Boot will be serviced by IOP1 or IOP2 (verify
this IOP is indeed in the "booting tuple.")
f. After several moments, NTLDR program will starts and you
will receive a message to depress the space bar to load the
"Last Known Good" configuration. (Note that the time
window allowed for depressing of space bar can be rather
short. Be ready.) Then boots NT with "Last Known Good"
configuration.
g. Power on the other CE to join the Marathon system.