> The O'Reilly Linux Server Security book's a good read if you have at > least a little Unix admin/user experience. It re-iterates a lot of the > good advice that's been covered on the list about securing SSH by > running on a non-standard port, only allowing key based auth and then > only for a limited subset of users/groups. > They also cover bastion firewalling. Essentially, anything internet > facing (or security sensitive), even if behind another firewall, it's > good practice to firewall to the hilt. The more layers the better. > Secure your OS. Secure your apps. Secure your network. A lot of it's > just common sense. Unless you're full time job is nothing but security > and you can track all the current vulnerabilities and infer where the > next ones will be just assume every thing's a risk and lock > down/remove everything you don't absolutely require to mitigate the > likelihood of getting owned. > Link-wise, I'd say the more you read the better. > http://www.google.co.uk/search?hl=en&q=hardening+linux&btnG=Search&meta= > http://www.google.co.uk/search?hl=en&q=hardening+redhat&btnG=Search&meta= > Start with those. :) > Bear in mind, if you're messing with stuff you're not sure about, use > a test machine/have backups/make sure you can reinstall from scratch > if you break somethign or get burned somehow. > Will. Thanks Will. One thing I have always done with SSH is run it on a non-default port. Its funny I left it on 22 once and watched the log reports every morning in my email for a few days and the amount of people trying to login as the root user was amazing... the report was 40-50 lines longer than normal just from all the attempts... I then chose a port over 10000 as they say most port scanners usually scan port 1-10000. Once I did that I have not seen one attempt to try and access root through SSH or any user for that matter. Good tip though... =) And yeah I always have a test machine for breaking stuff on... I think thats how I have learnt most of what I know about linux is breaking it and re-installing it many many times ;) Thanks for the info, very much appreciated... Gonna check out EBAY for that book and check out those links so I have some reading to do.. thanks again! James