Safemode - HP ProCurve 7000dl Series Basic Management And Configuration Manual

Overview
Software Overview
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SafeMode

SafeMode is a CLI feature that allows you to perform configuration changes
without the fear of being disconnected from a Telnet or SSH session. Some
configuration changes can interrupt network connectivity. If you are
managing a router remotely via SSH or Telnet, you can inadvertently lose your
connection to the router.
For example, you may need to apply an ACL, but this ACL doesn't allow Telnet
or SSH traffic. Once you applied the ACL, you would be locked out of the
router. In order to fix the configuration that has locked you out, you would
need physical access to the router so that you could establish a console session
with it. SafeMode allows you to make configuration changes using Telnet or
SSH without worrying about losing your connection and being unable to
reestablish it.
SafeMode requires you to periodically reset a reload timer. If the reload timer
runs out before you reset it, the Secure Router OS will assume that the current
running configuration has disrupted your connection to the router. It will save
the running-config to internal flash as "problem-config" and reboot the router.
Once the router has reloaded, it will display a reboot cause message and load
the currently saved startup-configuration file. The startup-config should allow
you to regain access to the router. You will then be able to review the saved
problem-config file and correct the setting that caused the disruption.
After you enable SafeMode and set the time limit, a reload timer is activated
for the Telnet and SSH access lines and begins to count down. You also set a
threshold timer, which is shorter than the reload timer. When the threshold
timer expires, a warning message is displayed in the CLI that allows you to
reset the timer. Unless you enter the reset keystroke before the reload timer
finishes counting down, the router reboots. This prevents you from being
locked out of the router if you lose the connection and are unable to reset the
timer.
While SafeMode is enabled, it temporarily suspends AutoSynch functioning.
This prevents a disruptive configuration from being saved to both flash and
compact flash. After the SafeMode configuration is complete and you have
disabled the SafeMode counter, the AutoSynch function, if previously enabled,
will automatically re-enable and begin synchronization.