[Nottingham] sshd - POSSIBLE BREAK-IN ATTEMPT!

[Martin]

I've seen many attempts on ssh but never noticed this before:

Jun 29 11:46:28 - sshd[3990]: Failed password for invalid user angel
from 71.16.200.56 port 43521 ssh2
Jun 29 11:46:29 - sshd[3995]: Address 71.16.200.56 maps to
uslec-71.16.200.56.cust.uslec.net, but this does not map back to the
address - POSSIBLE BREAK-IN ATTEMPT!


What's that variation?
Where's ssh getting its mappings from?

Cheers all,
Martin

-- 
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Martin Lomas
martin at ml1.co.uk
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