Warn for instances living on offline nodes
Warn for instances living on offline nodes

The patch also changes the result to error for non-reachable secondary nodes
(as for primary nodes).

Reviewed-by: ultrotter

leshchevds/ganeti,grnet/snf-ganeti,andir/ganeti,onponomarev/ganeti,grnet/snf-ganeti,apyrgio/snf-ganeti,ganeti-github-testing/ganeti-test-1,ganeti/ganeti,bitemyapp/ganeti,mbakke/ganeti,yiannist/ganeti,mbakke/ganeti,andir/ganeti,yiannist/ganeti,leshchevds/ganeti,ganeti-github-testing/ganeti-test-1,leshchevds/ganeti,ganeti/ganeti,apyrgio/ganeti,andir/ganeti,onponomarev/ganeti,dimara/ganeti,ganeti/ganeti,yiannist/ganeti,apyrgio/snf-ganeti,mbakke/ganeti,dimara/ganeti,apyrgio/ganeti,bitemyapp/ganeti