Update ganeti

howto/ganeti.md

@@ -222,6 +222,126 @@ Finally resize the filesystem:
 
 See also the [LVM howto](howto/lvm).
 
+#### What if lvm is not available?
+
+If is possible to resize a partition using fdisk. In the following example we have a sda1 partition that we want to extend from 10G to 20G to fill up the free space on /dev/sda
+
+```
+# lsblk -a
+NAME   MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
+fd0      2:0    1   4K  0 disk 
+sda      8:0    0  20G  0 disk 
+└─sda1   8:1    0  10G  0 part /
+sdb      8:16   0   2G  0 disk [SWAP]
+sdc      8:32   0  40G  0 disk /srv
+
+```
+
+We use fdisk on the device:
+
+```
+# fdisk /dev/sda
+
+Welcome to fdisk (util-linux 2.33.1).
+Changes will remain in memory only, until you decide to write them.
+Be careful before using the write command.
+
+
+Command (m for help): p # prints the partition table
+Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors
+Disk model: QEMU HARDDISK   
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 512 bytes
+I/O size (minimum/optimal): 512 bytes / 512 bytes
+Disklabel type: dos
+Disk identifier: 0x73ab5f76
+
+Device     Boot Start      End  Sectors Size Id Type
+/dev/sda1  *     2048 20971519 20969472  10G 83 Linux # note the starting sector for later
+
+```
+
+Now we delete the partition. Note that the data will not be delete only the partition table will be altered.
+
+```
+Command (m for help): d
+Selected partition 1
+Partition 1 has been deleted.
+
+Command (m for help): p
+Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors
+Disk model: QEMU HARDDISK   
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 512 bytes
+I/O size (minimum/optimal): 512 bytes / 512 bytes
+Disklabel type: dos
+Disk identifier: 0x73ab5f76
+```
+
+Now we create the new partition:
+
+```
+Command (m for help): n
+Partition type
+   p   primary (0 primary, 0 extended, 4 free)
+   e   extended (container for logical partitions)
+Select (default p): p
+Partition number (1-4, default 1): 1
+First sector (2048-41943039, default 2048): 2048 # this is the starting sector from above.
+Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-41943039, default 41943039): 41943039
+
+Created a new partition 1 of type 'Linux' and of size 20 GiB.
+Partition #1 contains a ext4 signature.
+
+Do you want to remove the signature? [Y]es/[N]o: n # we want to keep the previous signature
+
+Command (m for help): p
+
+Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors
+Disk model: QEMU HARDDISK   
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 512 bytes
+I/O size (minimum/optimal): 512 bytes / 512 bytes
+Disklabel type: dos
+Disk identifier: 0x73ab5f76
+
+Device     Boot Start      End  Sectors Size Id Type
+/dev/sda1        2048 41943039 41940992  20G 83 Linux
+
+Command (m for help): w
+The partition table has been altered.
+Syncing disks.
+```
+Now we check the partitions for the machine:
+
+```
+# lsblk -a
+NAME   MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
+fd0      2:0    1   4K  0 disk 
+sda      8:0    0  20G  0 disk 
+└─sda1   8:1    0  20G  0 part /
+sdb      8:16   0   2G  0 disk [SWAP]
+sdc      8:32   0  40G  0 disk /srv
+```
+
+If we check the free disk space on the device we will notice it has not changed  yet:
+```
+# df -h /
+Filesystem      Size  Used Avail Use% Mounted on
+/dev/sda1       9.8G  8.5G  874M  91% /
+```
+
+We need to resize it:
+
+```
+# resize2fs /dev/sda1
+resize2fs 1.44.5 (15-Dec-2018)
+Filesystem at /dev/sda1 is mounted on /; on-line resizing required
+old_desc_blocks = 2, new_desc_blocks = 3
+The filesystem on /dev/sda1 is now 5242624 (4k) blocks long.
+```
+
+
 ### Adding disks
 
 A disk can be added to an instance with the `modify` command as