As per my previous reply, discarding the regex and just using string equality:

$ cat b1.bak
ssh-rsa CCCC/DDDD/knMQ== user@host2.f.q.d.n
ssh-rsa AAAA/BBBB/kPW+Yi9yZ7Kh0mL/knMQ== user@host.f.q.d.n

$ perl -lne 'print unless $_ eq q(ssh-rsa AAAA/BBBB/kPW+Yi9yZ7Kh0mL/kn
+MQ== user@host.f.q.d.n)' b1.bak
ssh-rsa CCCC/DDDD/knMQ== user@host2.f.q.d.n

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In reply to Re^2: One liner: remove ssh keys with quotemeta by hippo
in thread One liner: remove ssh keys with quotemeta by Anonymous Monk

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