Internal networks can be used for direct communication between VMs.
- Click on the „Create Network“ button and assign a name for the network in the first tab, e.g., INTERN_1.
- In the Subnet tab, set a name for the subnet and the network range.
Example:
Subnet Name: Subnet_1
Network Address: 10.230.1.0/24
Gateway IP: will be automatically set to 10.230.1.1 in this example if the field is left empty.
DHCP: In the Subnet Details tab, you can configure the automatic distribution of addresses via DHCP, as well as the DNS Name Servers and, if necessary, static routes.
Only assign addresses from the range 10.230.0.0/16 (e.g., 10.230.1.0/24 or 10.230.20.0/24), otherwise, the network will be deactivated!
Example:
Allocation Pools: 10.230.1.10,10.230.1.100 (assigns addresses in the range 10.230.1.10 to 10.230.1.100 to the VMs)
DNS Name Servers:
131.188.0.10
131.188.0.11
A router is required for the VMs to reach external networks.
- Click on the „Create Router“ button, assign a name to the router (e.g., rtr1), and select FAU-Extern under „External Network“.
- Then click on „Create Router“.
If an internal network has already been created, it can now be connected to the router as follows:
- In the Network → Router menu, click on the router, switch to the Interfaces tab, and click on Add Interface.
- Select a subnet here and click on „Submit“.
A floating IP is required to make a VM accessible from the university network, for example.
- Click on the „Allocate IP to Project“ button.
- In the „Pool“ tab, select the external network (FAU-Extern) and click „Allocate IP“.
- The allocated IP will appear in the list. To associate it with a VM, click on the „Associate“ button next to the IP.
- In the pop-up window, select the port to which the floating IP should be assigned and confirm.
Security groups define firewall rules for the VMs.
- Click on the „Create Security Group“ button and provide a name and description.
- Click on the newly created security group and switch to the „Rules“ tab.
- Click on „Add Rule“ to define new inbound/outbound rules.
Example: allow SSH and ICMP
- Rule: SSH
- Direction: Ingress
- CIDR: 0.0.0.0/0
- Rule: ICMP
- Direction: Ingress
- CIDR: 0.0.0.0/0
Key pairs are used for SSH access to VMs.
- Click on the „Create Key Pair“ button.
- Provide a name for the key pair and click „Create Key Pair“.
- The private key (.pem file) will be downloaded automatically. Keep it secure as it is required for SSH access.
Use Key Pairs
to use a key pair on instance start:
- In the „Key Pair“ tab during instance startup, select the desired key pair.
Instances are virtual machines (VMs) in the cloud.
- Click on the „Launch Instance“ button and enter a Name for the Instance.
- You can select the number of instances via the Count Option. The given name receives incrementing numbers for each vm.
- In the „Source“ tab, select the boot source (e.g., image, volume) and the desired disk size.
- In the „Flavor“ tab, select the instance type based on vCPU, RAM, and disk requirements.
- In the „Networks“ tab, select the desired networks to which the instance should be connected.
- In the „Security Groups“ tab, select the security groups to apply.
- In the „Key Pair“ tab, select the previously created key pair.
- Click on „Launch Instance“ to start the VM.
If a floating IP was assigned to the instance, the instance is is now reachable via the given IP.
Accessing VMs via SSH
to access an Instance via SSH, a floating IP has to be assigned and a vaild keypair
- Open a terminal and issue the following command:
ssh -i path/to/private_key.pem username@floating_ip
Beispiel:
ssh -i ~/.ssh/mykey.pem ubuntu@172.17.66.12
Special Case: Windows VM
Specifying the key files is also relevant for Windows images.
After the VM is created, you can check through the console (click on the VM in the instance overview and switch to the console tab) when the VM is at the Windows login screen. Then, you can use the „RETRIEVE PASSWORD“ option from the dropdown menu of the VM in the instance overview to get the Windows login password.
For this, you will need the private key part corresponding to the public key stored with the VM. Select this in the dialog via „Choose File“ and click on „Decrypt Password“.
The password will now be displayed.
Then, in the console of the VM, cancel the prompt to change the password and use the decrypted password to log in.
Rescue VM (Rescue System)
In the instance overview (Menu Compute -> Instances), click on the dropdown menu next to the VM and select „Rescue Instance“.
This will attach a „grml“ ISO to the VM.
Disks are block storage devices that can be attached to instances.
- Click on the „Create Volume“ button.
- Provide a name, description, and size for the disk.
- Click on „Create Volume“.
To attach a volume to an instance:
- Navigate to the Compute -> Instances menu.
- Click on the dropdown menu next to the desired instance and select „Attach Volume“.
- Select the disk and click on „Attach Volume“.
Snapshots are point-in-time images of instances that can be used for backups or to create new instances.
- Click on the „Create Snapshot“ button next to the desired instance.
- Provide a name and description for the snapshot and click on „Create Snapshot“.
Use Snapshots
To start an instance from a snapshot:
- In the „Source“ tab during instance startup, select „Snapshot“ and choose the desired snapshot.
- Click on the „CREATE CLUSTER“ button and in the first screen (Details), assign a name for the cluster, select a template with the desired version, and assign a key pair for access.
- In the Size screen, set the number of desired master and worker nodes and select the desired flavor for each. Through the Auto Scaling option, you can define a minimum and maximum number of worker nodes, which will be scaled up or down as needed.
- In the Network screen, you can enable a load balancer for the master nodes and either create a new network or use an existing one. Additionally, you can set whether the Cluster API is „public“ (not recommended) or only accessible from your private networks.
- In the Management screen, you can enable automatic node repair.
Once all relevant settings are configured, the cluster can be started by clicking the „SUBMIT“ button.
See also: https://www.anleitungen.rrze.fau.de/serverdienste/cc/compute-cloud-cc-kaas/
