ocp

redhat/notes/2023/2023.10.qcow2.modify.md

@@ -0,0 +1,42 @@
+# modify qcow2
+
+```bash
+# https://platform9.com/blog/how-to-create-customized-qcow-images/
+qemu-img info rhcos-openstack.x86_64.qcow2
+# image: rhcos-openstack.x86_64.qcow2
+# file format: qcow2
+# virtual size: 16 GiB (17179869184 bytes)
+# disk size: 2.46 GiB
+# cluster_size: 65536
+# Format specific information:
+#     compat: 1.1
+#     compression type: zlib
+#     lazy refcounts: false
+#     refcount bits: 16
+#     corrupt: false
+#     extended l2: false
+
+virt-filesystems --long -h -a rhcos-openstack.x86_64.qcow2
+# Name       Type        VFS   Label       Size  Parent
+# /dev/sda2  filesystem  vfat  EFI-SYSTEM  127M  -
+# /dev/sda3  filesystem  ext4  boot        350M  -
+# /dev/sda4  filesystem  xfs   root        3.3G  -
+
+
+# https://docs.openstack.org/image-guide/modify-images.html
+modprobe nbd max_part=16
+
+qemu-nbd -c /dev/nbd0 rhcos-openstack.x86_64.qcow2
+
+partprobe /dev/nbd0
+
+ls -l /dev/nbd0*
+# brw-rw----. 1 root disk 43, 0 Oct 12 13:55 /dev/nbd0
+# brw-rw----. 1 root disk 43, 1 Oct 12 13:55 /dev/nbd0p1
+# brw-rw----. 1 root disk 43, 2 Oct 12 13:55 /dev/nbd0p2
+# brw-rw----. 1 root disk 43, 3 Oct 12 13:55 /dev/nbd0p3
+# brw-rw----. 1 root disk 43, 4 Oct 12 13:55 /dev/nbd0p4
+
+mount /dev/nbd0p2 /mnt/2
+
+```