Posts: Add new posts

_posts/2023/2023-02-15-cobbler-inside-libvirt-1.md

@@ -0,0 +1,129 @@
+---
+layout: post
+title: Cobbler inside libvirt (1)
+author: Enno
+summary: Cobbler inside libvirt with a private libvirt network
+---
+
+The last blog post that was neither a roadmap update or a release announcement was in december of 2020. Thus it is time
+to give you guys a new guide!
+
+This time we will together explore how to use Cobbler to enable a libvirt internal network to boot over the network.
+The guide will assume you have a running host OS and libvirt installed and running already. As a guest OS I will use
+openSUSE Tumbleweed but any other guest OS should work equally good.
+
+In case you have libvirt not installed please consult your OS vendors resources to do so. A few examples:
+
+- [openSUSE](https://doc.opensuse.org/documentation/leap/virtualization/html/book-virtualization/part-virt-libvirt.html)
+- [Fedora](https://developer.fedoraproject.org/tools/virtualization/installing-libvirt-and-virt-install-on-fedora-linux.html)
+- [Ubuntu](https://ubuntu.com/server/docs/virtualization-libvirt)
+
+Note:
+
+> There will be a second part of this guide where we will utilize a network bridge to also boot real hardware with our
+> VM based Cobbler setup.
+
+Information:
+
+> Depending on your setup you may need to prefix the `virsh` and other commands with `sudo`.
+
+1. Create libvirt network for Cobbler (don't use the network `default`).
+   ```xml
+   <network>xml
+     <name>cobbler</name>
+     <uuid>6b7f4f36-7895-4b74-8be6-dfa4b2b84500</uuid>
+     <forward mode='nat'/>
+     <bridge name='virbr2' stp='on' delay='0'/>
+     <mac address='52:54:00:fb:72:57'/>
+     <domain name='cobbler.local'/>
+     <dns enable='no'/>
+     <ip family='ipv4' address='10.17.3.1' prefix='24'>
+     </ip>
+   </network>
+   ```
+2. Download the openSUSE Tumbleweed ISO and move it to your desired libvirt storage pool (below I show the default
+   location):
+   ```
+   wget https://download.opensuse.org/tumbleweed/iso/openSUSE-Tumbleweed-NET-x86_64-Current.iso
+   mv openSUSE-Tumbleweed-NET-x86_64-Current.iso /var/lib/libvirt/images
+   ```
+3. Setup the guest. An example for a guide can be found [in the openSUSE Documentation](https://doc.opensuse.org/documentation/leap/virtualization/html/book-virtualization/cha-kvm-inst.html#sec-libvirt-inst-vmm).
+4. Login into the guest either via SSH or if you are using `virt-manager` using the GUI.
+5. `zypper in cobbler` (atm 3.3.3)
+6. Shutdown the VM from the host
+   ```
+   virsh shutdown "<vm name>"
+   ```
+   or if you are logged into the guest use
+   ```
+   systemctl poweroff
+   ```
+7. Add a second network to the guest. Use the network defined in step 1.
+8. Start the VM again use the UI of `virt-manager` or use
+   ```
+   virsh start "<vm name>"
+   ```
+9.  Log into the VM after it started using SSH (easier to copy & paste between host and guest).
+    ```
+    ssh [email protected]
+    ```
+10. Setup the secondary network interface that is inside the network that Cobbler is managing:
+    ```
+    ip a add 10.17.3.2/24 dev eth1
+    ip link set dev eth1 up
+    ip route add 10.17.3.0/24 via 10.17.3.1
+    ```
+    You will need to adjust the name of the interface `eth1` to the interface that doesn't belong to the default NAT
+    network.
+11. Edit Cobbler settings to match IP on guest (and thus subnet):
+    ```yml
+    server: 10.17.3.2
+    next_server_v4: 10.17.3.2
+    manage_dhcp: true
+    manage_dhcp_v4: true
+    ```
+12. Restart Cobbler
+    ```
+    systemctl restart cobblerd
+    ```
+13. Download the openSUSE Leap image (or any other full DVD ISO) inside the Cobbler VM:
+    ```
+    wget https://download.opensuse.org/distribution/leap/15.4/iso/openSUSE-Leap-15.4-DVD-x86_64-Media.iso
+    ```
+14. Mount the ISO to a reasonable directory:
+    ```
+    mkdir -p /mnt/cobbler-isos/leap-15-4
+    mount -o loop /root/openSUSE-Leap-15.4-DVD-x86_64-Media.iso /mnt/cobbler-isos/leap-15-4
+    ```
+15. Use `cobbler import` to automate setting up a distro and profile:
+    ```
+    cobbler import --name="openSUSE-Leap-15-4" --path="/mnt/cobbler-isos/leap-15-4/"
+    ```
+16. Setup an emtpy VM - no installation media required. Make note of the MAC address of the VM.
+17. Add the system to Cobbler:
+    ```
+    cobbler system add --name="testsystem" --profile="openSUSE-Leap-15-4-x86_64" --mac="<your mac here>" --ip="10.17.3.20"
+    ```
+18. Generate the bootloaders and sync them into the TFTP Tree
+    ```
+    cobbler mkloaders && cobbler sync
+    ```
+19. Profit
+
+To clean up after your experiments there are only a couple of commands needed:
+
+```
+virsh destroy <vm name> && virsh destroy <second vm name> && virsh net-destroy cobbler
+```
+
+Further topics:
+
+- Write autoinstall snippets for your setups
+- Setup Windows Guests
+- Don't forget to set netboot_enabled to `False`
+
+---
+
+P.S.: In case your find typos and/or grammar mistakes just
+[open an Issue](https://github.com/cobbler/cobbler.github.io/issues/new) or
+[open a PR](https://github.com/cobbler/cobbler.github.io/compare).

_posts/2023/2023-02-16-cobbler-inside-libvirt-2.md

@@ -0,0 +1,27 @@
+---
+layout: post
+title: Cobbler inside libvirt (2)
+author: Enno
+summary: Cobbler inside libvirt with a network bridge
+---
+
+- Assume part 1 is read
+- Assume DHCP is handled externally
+- Setup libvirt bridge
+- Install guest OS
+- Install Cobbler
+- Do settings to match IP range
+- Restart Cobbler
+- Add SSH keys
+- Login from host via SSH
+- wget leap DVD ISO
+- cobbler import
+- cobbler system add
+- cobbler sync
+- Setup emtpy VM with bridge network
+
+---
+
+P.S.: In case your find typos and/or grammar mistakes just
+[open an Issue](https://github.com/cobbler/cobbler.github.io/issues/new) or
+[open a PR](https://github.com/cobbler/cobbler.github.io/compare).