Changing the location of mapcache

a) You may need to post install with domain account
b) any machine could have the cache, but the domain account should have access to that machine.. give full rights to the domain account for that map cache folder
c) one time cache creation is enough, you could move anywhere.
e) use unified naming convention to access the map cache folder (\\machine2\arcgisserver\arcgiscache)
d) use arcgis server manager to change the cache directories.. dont use arccatalog
e) but ensure that the map cache directory are addeded in the server using arccatalog.

For more help, ping me vadivelan.gis@gmail.com.