Does a thumb rule exists for “server administrators to a number of servers for a large and distributed enterprise infrastructure.”
I know this cannot be applied in every situation, but is there some reference than can be used to derive a head count for 24×7 support operations.
1) check out the paper: “How Many Administrators are Enough” http://www.verber.com/mark/sysadm/how-many-admins.html
2) If there is a remote mangement tool to access the same. then the number is around 200-300.
if no software is present and physical present is required, then not more than 50-100 servers per server administrator. I am assuming these servers to be windows servers.
in case of Unix boxes, more servers can be managed even without management software, as patches to be applied are less often and they hardly need to be rebooted. so zero admin scenarios can exisit with unix boxes.
3) Administrators vs no. of servers depends on the stability of the organization and the stability of the OS being used. I have driven an initiative where I could drive the ratio from 150 per SA to 900 per SA. This involved a lot of standardization on the OS level as well as a focus effort to reduce known problems and working on eradication of the problems rather than break fix efforts. A lot of focus was also driven on the quality and training of the SA’s.
Source: LinkedIn Answers (March 2008) http://www.linkedin.com/answers/hiring-human-resources/staffing-recruiting/HRH_SFF/184490-5730787?browseCategory=&goback=.ahp