New version of syslock (1.12): supports append-only flag management; sample config for BSD & Linux sets append-only on process accounting live log and immutable for historical logs and provides instruction on how to unlock and relock for log rotation for OpenBSD & Proxmox. https://github.com/lippard661/syslock
GitHub - lippard661/syslock: syslock and sysunlock script for managing filesystem immutable flags

syslock and sysunlock script for managing filesystem immutable flags - lippard661/syslock

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Sample config defines a group called "acct" for BSD, "pacct" for Linux; syslock -g acct (or pacct) will set append-only on the live log and immutable on the rest, unlocked with sysunlock -g acct (or pacct).