Problem
Receiving "illegal base64 data at input byte X" error when reaching the "/sys/storage/raft/snapshot-auto/status/:name" endpoint while using Azure blob snapshot type. The character "X" in the error indicates the byte number, for example - byte 6.
Prerequisites (if applicable)
Vault version that support the automated snapshot feature.
Cause
The value of azure_account_key parameter of the /sys/storage/raft/snapshot-auto/config/:name endpoint contains an illegal character at the specified byte number. The count will start at 0, for example, if the literal error is - "illegal base64 data at input byte 6", the illegal character will be located at position 7.
Solution
Verify the validity of both the azure_account_key and the azure_account_name parameters used for configuring the auto-snapshot.
Outcome
After correcting the value of the azure_account_key parameter, the error should not appear when requesting the "/sys/storage/raft/snapshot-auto/status/:name" endpoint.