RHCA/RHCE certification mandatory ( know how of Linux security is a must)
MCSE certification is an added bonus
Strong concepts in Networking , core OS concepts and active directories/LDAP etc
Good understanding of Public Key infrastructure.
Proficient in concept around cryptographic keys, digital signature , hashing, encryption etc.
Expert in Python/Shell or Perl. ( any scripting language ). Powershell is an added bonus.
Should be able to write scripts to build OS baselines across large enterprise platforms.
Ability to translate high level design into LLD and implement the infrastructure.
Exp. with openSSH added advantage