There are two other ways to lock yourself out, thus requiring a fw unloadlocal to recover, as these are checked before even the implied rules:
1) Antispoofing topology mistake that blocks traffic from the subnet where the SMS is located.
2) Adding a SAM rule from the SmartView Monitor or fw sam command that blocks traffic from the subnet where the SMS is located.
For situation #1 antispoofing enforcement can be disabled in the fly without incurring a full outage, by running the following commands on R80.30 Jumbo HFA Take 71 or later:
fw ctl set int fw_antispoofing_enabled 0
fw ctl set int sim_anti_spoofing_enabled 0 -a
This capability may have been backported into a Jumbo HFA of R80.20 at some point, not sure.
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