I used to think that the Redhat security guides were good [1], but would also go through the NSA guide to securing Redhat [2]. Seems a little ironic nowadays.
Recently, we had Bryan Kennedy's "first 5 minutes" [3], linked from Drew Crawford's guide to "NSA proofing" email [4] (pretty good guide to securing a mail server).
Recently, we had Bryan Kennedy's "first 5 minutes" [3], linked from Drew Crawford's guide to "NSA proofing" email [4] (pretty good guide to securing a mail server).
[1] https://access.redhat.com/site/documentation/Red_Hat_Enterpr... [2] http://www.nsa.gov/ia/mitigation_guidance/security_configura... [3] http://plusbryan.com/my-first-5-minutes-on-a-server-or-essen... [4] http://sealedabstract.com/code/nsa-proof-your-e-mail-in-2-ho...