linux-ops

Save runtime and persistent rules, arm a privileged detached rollback timer independent of the SSH session, validate the candidate with nft -c, then apply and test a fresh non-multiplexed SSH connection on both IPv4 and IPv6 before cancelling the rollback.

A deleted file still consumes blocks while any process holds it open; the space is reclaimed only when the last holder closes it. Use lsof +L1 to find holders grouped by device and inode, then use the application's documented reopen mechanism instead of truncating proc FDs.

No. daemon-reload reloads unit definitions into the manager but does not retrofit mount namespaces, credentials, capabilities, or limits into the existing MainPID. Execution-policy changes require an approved drain and restart of the affected process.

Not blindly. Programs using select(2) cannot safely handle descriptors above 1023, so raising the limit can cause memory corruption instead of clean capacity failures. Confirm the polling backend first and inspect /proc/PID/limits on the live process.

Select snapshots by explicit ID, host, and path rather than unqualified latest, and compute recoverable age at incident time. Structural checks and even --read-data do not prove application usability or RTO; only a timed isolated restore with application validation does.

Do not use it for cloud IAM or provider networking, container and Kubernetes resources, application-level code bugs, or database-consistent backup protocols. Those belong to the respective cloud, container, language, or database skills.