It is difficult to explain all the internel workings of the SRM, vsphere replication etc... in this short time....
the basics are simple... how it works..?
there are 2 types of replication 1- vsphere replication 2- Array based replication
vpshere replication is an agent based - that is a VR agent will be there inside the esxi hosts this agent monitor the VM's running inside that host, and replicates the data to remote site though WAN link.
the main pointh here is - once the replication of the entire VM happened, after that only the changed blocks of the VMFS will be replicated... that is the only the changed data of the vm will be replicated. it is called CBT, the VR agent tracks the blocks inside the VMFS, if any data block of the VM is changed it will get replicated.
the vsphere replication dosent require any support from the underlying storage array...
the second one is the array based one... where the entire replication is handled by the Storage array... and this will work with the SRM..
refer the post for more details.. http://communities.vmware.com/message/2175005#2175005
now to your questions -
1. Does anyone have any good tutorials on this. - the best method is to read the official docs...
http://www.vmware.com/files/pdf/techpaper/Introduction-to-vSphere-Replication.pdf
http://blogs.vmware.com/vsphere/2012/08/srm-5-1-and-vsphere-replication-as-a-standalone-feature.html
http://thesaffageek.co.uk/2012/08/27/vsphere-5-1-announced-with-enhanced-vsphere-replication/
2. I've gone and done a schoolboy error I think, I have given the vSphere replicaiton appliance the same IP as my ESXi host. (This is how much I am struggling) and now I can not access the host machine because of this. Can anyone tell me how I can reconnect to this machine without a complete reinstall and rebuild of the 50 or so hosts.
if the esx host is in cluster, by using ILO and esxi shell put the host in maintenence mode... and reset the esxi
To enter maintenance mode run the following command
vmware-vim-cmd /hostsvc/maintenance_mode_enter
and
To exit maintenance mode run the following command
vmware-vim-cmd /hostsvc/maintenance_mode_exit
then reboot the esxi host and give the correct ip, or power off the VR applicance and give correct ip