zlacker

>>belter+(OP)
I used to do remote work in firewalls quite often, and after locking myself out once or twice, I came up with a new habit: before making any changes I would schedule a reboot for 5min out which would revert any changes. That way if I locked myself out I could just wait for the reboot and get back in.

>>Nifty3+5n1
I did a similar thing in the early days of my career, but I actually caused an outage as a result.

In this instance, I was adding itables rules to a host. I wrote a script that add all the rules to enable expected network traffic, then set the default policy to DROP. Before running this script, I scheduled another script to be run which would delete all the rules I'd added. I did not remember to set the default policy to ALLOW.

The script runs, everything looks good. Five minutes later, pagers start going off.

Thankfully we were able to remotely power-cycle the host and didn't have to drive down to the datacenter in order to fix the issue.