netdiff [diff-options] [host1:]path1 [host2:]path2
This tool works exactly like diff(1), except that a file or directory specification may be preceded by a colon-delimited hostname in the style of ssh or scp. If so, it makes a temporary copy of the file or directory locally in order to perform the diff.
All options are simply passed to the diff command.
You will be required to authenticate to remote machines. To reduce friction it is best to have your ssh keys installed on all machines across which you use this tool.
netdiff is written in pure POSIX shell. It requires a POSIX-compliant expr(1). It uses scp(1) as a transport.
Filenames containing "%" will confuse it. File content on either side of a link that matches the pattern of either of the tempfile names will also confuse it.
There is a different "netdiff" that is a Python library for network analysis, but the analogy of this tool with netcat(1) was impossible to resist.
Same as diff(1); return 1 may also be caused by a network copy failure.
diff(1), netcat(1), scp(1).