SSH debug output can be quite misleading.
When you see the following output, it does NOT indicate a problem.
debug2: key_type_from_name: unknown key type '-----BEGIN'
debug3: key_read: missing keytype
debug3: key_read: missing whitespace
...
debug2: key_type_from_name: unknown key type '-----END'
debug3: key_read: missing keytype
debug1: identity file /home/foo/.ssh/id_rsa type 1
The final line tells you that the key was read successfully.
(source)
See also another ssh non-error.
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