I'm really new to this. I've been struggling with how to keep multiple webservers synced. It seems like DRBD8 and OCFS2 is the way to go. However, every example I see so far keeps referencing dual-primary and two nodes. I don't see anything indicating this is the way to go for say 5-10 webservers. So the question is mostly, can DRBD8 be used to sync 5-10 web servers and would it be good in an environment were we frequently add/remove web servers?
DRBD 8.x does only support two nodes, if you count the stacking option, it's up to 4 nodes. So it's not a solution for syncing data of 5-10 webservers. The upcoming DRBD version 9 will support up to 32 nodes. Another solution would be to use a cluster file system like GFS or GlusterFS, see: http://en.wikipedia.org/wiki/Clustered_file_system