Use the new dry-run mode in cmdlib

This will hopefully detect potential LVM (or any other storage, when
they implement it) issues before committing changes just on some
nodes.

Unfortunately due to the dry_run opcode handling, we can't integrate
this into the usual handling (as we need to activate the disks before
doing any tests, which belongs in Exec not in CheckPrereq).

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>

diff --git a/lib/cmdlib.py b/lib/cmdlib.py
index b8f423f..7ba8630 100644 (file)
--- a/lib/cmdlib.py
+++ b/lib/cmdlib.py
@@ -9517,6 +9517,14 @@ class LUInstanceGrowDisk(LogicalUnit):
     if not disks_ok:
       raise errors.OpExecError("Cannot activate block device to grow")
 
+    # First run all grow ops in dry-run mode
+    for node in instance.all_nodes:
+      self.cfg.SetDiskID(disk, node)
+      result = self.rpc.call_blockdev_grow(node, disk, self.op.amount, True)
+      result.Raise("Grow request failed to node %s" % node)
+
+    # We know that (as far as we can test) operations across different
+    # nodes will succeed, time to run it for real
     for node in instance.all_nodes:
       self.cfg.SetDiskID(disk, node)
       result = self.rpc.call_blockdev_grow(node, disk, self.op.amount, False)