Allow configdrive partition to be precreated

jayofdoom · jayofdoom · commit a7d68658838e · 2014-06-03T16:52:33.000-07:00
This adds support for copying configdrives to disks that already have
partitions enabled and labeled for configdrives. This is neccessary for
supporting configdrives on partitioning schemes we don't support yet
(like GPT) or for some future agent iteration where we create partitions
separately.

Change-Id: Iee5b87d82be08febc495aaef3272ced4f2f32235
diff --git a/ironic_python_agent/shell/copy_configdrive_to_disk.sh b/ironic_python_agent/shell/copy_configdrive_to_disk.sh
@@ -34,15 +34,21 @@ DEVICE="$2"
 [[ -f $CONFIGDRIVE ]] || usage "$CONFIGDRIVE (CONFIGDRIVE) is not a regular file"
 [[ -b $DEVICE ]] || usage "$DEVICE (DEVICE) is not a block device"
 
-# Create small partition at the end of the device
-log "Adding configdrive partition to $DEVICE"
-parted -a optimal -s -- $DEVICE mkpart primary ext2 -64MiB -0
-
-# Find partition we just created
-# Dump all partitions, ignore empty ones, then get the last partition ID
-ISO_PARTITION=`sfdisk --dump $DEVICE | grep -v ' 0,' | tail -n1 | awk '{print $1}'`
-
-# This generates the ISO image of the config drive.
+# Check for preexisting partition for configdrive
+EXISTING_PARTITION=`/sbin/blkid -l -o device $DEVICE -t LABEL=config-2`
+if [[ $? == 0 ]]; then
+  ISO_PARTITION=$EXISTING_PARTITION
+else
+  # Create small partition at the end of the device
+  log "Adding configdrive partition to $DEVICE"
+  parted -a optimal -s -- $DEVICE mkpart primary ext2 -64MiB -0
+
+  # Find partition we just created
+  # Dump all partitions, ignore empty ones, then get the last partition ID
+  ISO_PARTITION=`sfdisk --dump $DEVICE | grep -v ' 0,' | tail -n1 | awk '{print $1}'`
+fi
+
+# This writes the ISO image to the config drive.
 log "Writing Configdrive contents in $CONFIGDRIVE to $ISO_PARTITION"
 dd if=$CONFIGDRIVE of=$ISO_PARTITION bs=64K oflag=direct
 
