When using `scap sync-file`, I see 9 `mw` hosts that fail to get synced because of a permissions issue caused by `deploy1001`:
```
$ scap sync-file -v wmf-config/InitialiseSettings.php 'Switch a bulk of low-traffic jobs to EventBus for testwikis, file 1/2 (retry #2)'
12:39:26 Started sync-apaches
12:39:26 Using key: /etc/keyholder.d/mwdeploy.pub
12:39:31 ['/usr/bin/scap', 'pull', '--no-update-l10n', '--include', 'wmf-config', '--include', 'wmf-config/InitialiseSettings.php', '--verbose', 'mw1284.eqiad.wmnet', 'mw1319.eqiad.wmnet', 'mw1280.eqiad.wmnet', 'mw2290.codfw.wmnet', 'mw2215.codfw.wmnet', 'mw2254.codfw.wmnet', 'mw2187.codfw.wmnet', 'mw1250.eqiad.wmnet', 'mw1313.eqiad.wmnet'] on deploy1001.eqiad.wmnet returned [255]: Permission denied (publickey,keyboard-interactive).
sync-apaches: 100% (ok: 269; fail: 1; left: 0)
12:39:31 1 apaches had sync errors
12:39:31 Finished sync-apaches (duration: 00m 05s)
```