Real World Computing

Ian Wrigley and Simon Brock discuss how to keep your systems safe and secure from attacks Hackers are a fact of life these days. Anyone who's managed a server will know that the box will inevitably be probed, and logins attempted, on a daily basis. For example, on just one server we manage - which sits behind a firewall with only a very limited number of ports open - we've seen dozens of different login attempts from unauthorised sources over the last couple of days alone, including one sustained attempt to log in via SSH more than 2,500 times, and this is absolutely typical. So much so that these days we don't even bother notifying the system administrator of the machine from which the logins were attempted. Gone are those days when we'd email administrators to warn them that their own machines may be compromised.