Servers and infrastructure
Container registries, SSH transports, and version control on machines you do not fully administer - including the errors that are permission problems and the ones that only look like them.
- Synology NAS: scp fails with "subsystem request failed on channel 0"
DSM ships an SSH server without the sftp subsystem, so scp and sftp both fail even though ssh logs in fine. Transfer files with cat over ssh instead — and do not expect the bundled ffmpeg to encode anything.
- docker manifest inspect fails with "permission denied" on /etc/docker/certs.d
A deploy script that pre-checks whether an image tag exists breaks for non-root users on nodes with a private registry CA. The registry API answers anyway — use a plain HTTP HEAD as the fallback.
- Editing a Subversion repository without a working copy: svnmucc
Checking out a release repository just to change one deploy script is slow and error-prone. svnmucc performs put, rm and mv straight against the URL as one atomic commit — including the commit-message prefix a pre-commit hook may demand.