Two separate fixes from a live report.
1. The DR-spare and SFTP-mirror sections both checked ONLY /root/.ssh
for a key, missing the common case: the person running `sudo
./setup.sh backup` already has a key under their own home directory
(used interactively, quite possibly already authorized on the target
box), while root — who actually runs the scheduled systemd service —
has none. Confirmed live: "the computer has the ssh key for the sudo
user on the box" produced "No SSH key found for root" with no
inline way to do anything about it beyond a pointer to go set one up
elsewhere and re-run.
Factored both call sites into one shared _backup_ensure_root_ssh_key()
that checks root first, then offers to reuse the sudo user's existing
keypair (copied into /root/.ssh with correct ownership/permissions,
root:root 600) before falling back to generating a brand new one —
reusing an existing key can work immediately if it's already
authorized on the target, where a fresh key needs a new ssh-copy-id
round-trip regardless. Verified all three branches (root already has
a key, root has none but the user does and accepts reuse, neither
exists and one gets generated) against a mocked filesystem.
2. The B2 dry-run failure message read like it could be about missing
input even when every field was non-empty — confirmed there's no
code path where non-blank-but-wrong values actually trigger the
separate "Left blank" message (the two are on disjoint branches), but
the dry-run failure text itself didn't rule that out or point at the
actual likely cause. Now echoes back what was entered (bucket,
endpoint, Key ID — never the secret) so it's easy to eyeball against
B2's own confirmation screen, states plainly that this is a rejection
of non-blank input, and names the most likely cause directly: pairing
the Key ID from one Application Key with the Secret from a different
one, which is easy to do after creating more than one while
troubleshooting.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H4k6J1qXXyYxhGEgnJaMvn
Claude
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