De acordo com o manual do NixOps ...
Keys from deployment.keys are stored under /run/ on a temporary filesystem and will not persist across a reboot...Note that all nixops commands implicitly upload keys when appropriate, so manually sending keys should only be necessary after an unattended reboot.
Experimente o comando nixops send-keys .
nixops send-keys [ --include machine-name... ] [ --exclude machine-name... ]
Description
This command uploads the keys described in deployment.keys to remote machines in the /run/keys/ directory.
Keys are not persisted across reboots by default. If a machine reboot is triggered from outside nixops, it will need nixops send-keys to repopulate its keys.
Note that nixops deploy does an implicit send-keys where appropriate, so manually sending keys is only necessary after unattended reboots.
Options
--include machine-name...
Only operate on the machines explicitly mentioned here, excluding other machines.
--exclude machine-name...
Only operate on the machines that are not mentioned here.
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