An overview of the Packet Filter (PF) firewall in FreeBSD: rule syntax, tables, macros, anchors, logging, and real-world configuration examples with pfctl. Comments

An overview of the Packet Filter (PF) firewall in FreeBSD - configuration, rules and their application, macros, tables, anchors, logging, management with pfctl

I got this FreeBSD 14.3 instance that's using ufs. 1GB of ram, available between 60-40%. it's got / mounted read-only and /var is r/w in order to protect the filesystem against the unexpected. whenever I need to install new packages I `mount -u -o rw /`, do the install, sometimes tweak the packet filter, `pfctl -f /etc/pf.conf` and then `mount -u -o ro /`. most of the time this works without issues. however sometimes the ro remount takes a lot of time and I repeat the command the kernel oops-es. I need to force a restart of the instance from the ISP's control panel since `reboot` hangs. Unfortunately the crash never seems to get logged, even if the /var partition remains rw. What steps should I take to better debug this issue the next time it happens? and this is not a new regression, it was also happening with 14.2. thanks!