Move etcd - New Azure VM

Overview

This procedure is required for all clusters, including remote clusters, and is run on data nodes only.

The Kubernetes etcd database must be on a separate disk to give it access to all the resources required for optimal TOS performance, stability and minimal latency. We recommend performing this procedure after you install the operating system and before you install TOS.

This procedure must be performed by an experienced Linux administrator with knowledge of network configuration.

Preliminary Preparations

Switch to the root user.
```
[<ADMIN> ~]$ sudo su -
```
sudo su -
Install the rsync RPM.
```
[<ADMIN> ~]$ dnf install rsync
```
dnf install rsync
Find the name of the last disk added to the VM.
```
[<ADMIN> ~]# lsblk -ndl -o NAME
```
lsblk -ndl -o NAME
The output returns the list of disks on the VM. The last letter of the disk name indicates in which it was added, for example: sda, sdb, sdc.
Save the name of the last disk in a separate location. You will need it later for verification purposes.

Mount The etcd Database to a Separate Disk

Add a disk to the VM.
1. In the Azure VM, go to the Disks pane, and under Data Disks, click Create and Attach a new disk.
2. Configure the following settings:
  - Disk name
  - LUN
  - Storage type: Premium SSD LRS
  - Size: Allocate a disk size of at least 50 GB
  - Max IOPS: 7500
  - Max throughput: 250 MBps
  - Encryption: Use the default setting
  - Host caching: read/write
3. Click the Edit ()button, and in the Size field click the Change Size link.
4. Verify that the performance tier is P40.
5. Click OK.
Mount the new disk.
1. Log into the data node as the root user.
2. Verify that the new disk is recognized by the OS.
  [<ADMIN> ~]# lsblk
  
  lsblk
  [<ADMIN> ~]# ls -l /dev/sd*
  
  ls -l /dev/sd*
  Compare the output with the name of the disk you saved in the preliminary preparations, and verify that the disk name it returned ends with the next letter in the alphabet. For example, if the name you saved was sdb the output should return sdc. This indicates that the OS recognizes the new disk.
3. Create a variable with the block device path of the new disk.
  [<ADMIN> ~]# BLOCK_DEV="/dev/sd<>"
  
  BLOCK_DEV="/dev/sd<>"
  where <> represents the letter of the new disk.
4. Generate a UUID for the block device of the new disk.
  [<ADMIN> ~]# BLOCK_UUID="$(uuidgen)"
  
  BLOCK_UUID="$(uuidgen)"
5. Create a primary partition on the new disk.
  [<ADMIN> ~]# parted -s -a optimal ${BLOCK_DEV} mklabel msdos -- mkpart primary ext4 1MiB 100%
  
  parted -s -a optimal ${BLOCK_DEV} mklabel msdos -- mkpart primary ext4 1MiB 100%
6. Verify that the partition was created.
  [<ADMIN> ~]# parted -s ${BLOCK_DEV} print
  
  parted -s ${BLOCK_DEV} print
7. Format the partition as ext4.
  [<ADMIN> ~]# mkfs.ext4 -L ETCD -U ${BLOCK_UUID} ${BLOCK_DEV}1
  
  mkfs.ext4 -L ETCD -U ${BLOCK_UUID} ${BLOCK_DEV}1
8. Verify that the partition has been formatted with the UUID and the etcd label (output should return the partition with UUID and an ETCD label).
  [<ADMIN> ~]# blkid | grep "$BLOCK_UUID"
  
  blkid | grep "$BLOCK_UUID"
9. Create the mount point of the etcd database.
  [<ADMIN> ~]# mkdir -p /var/lib/rancher/k3s/server/db
  
  mkdir -p /var/lib/rancher/k3s/server/db
10. Set the partition to mount upon operating system startup.
  [<ADMIN> ~]# echo "UUID=${BLOCK_UUID} /var/lib/rancher/k3s/server/db ext4 defaults 0 0" >> /etc/fstab
  
  echo "UUID=${BLOCK_UUID} /var/lib/rancher/k3s/server/db ext4 defaults 0 0" >> /etc/fstab
11. Load the changes to the filesystem.
  [<ADMIN> ~]# systemctl daemon-reload
  
  systemctl daemon-reload
12. Mount the partition that was added to /etc/fstab.
  [<ADMIN> ~]# mount /var/lib/rancher/k3s/server/db
  
  mount /var/lib/rancher/k3s/server/db
  If the output is not empty, stop the procedure. The etcd disk cannot be mounted. Review what was missed in the previous steps.
13. Verify the partition has been mounted (the output should return the block device and mount point).
  [<ADMIN> ~]# mount | grep "/var/lib/rancher/k3s/server/db"
  
  mount | grep "/var/lib/rancher/k3s/server/db"
  If the output is empty, stop the procedure. The etcd disk is not mounted. Review what was missed in the previous steps.
Install TOS.

See Clean Install of TOS on Azure

Check the cluster status.

On the primary data node, check the TOS status.
```
[<ADMIN> ~]$ tos status
```
tos status
In the output, check if the System Status is Ok and all the items listed under Components appear as Ok. If this is not the case, contact Tufin Support.

Example output for a central cluster data node:

[<ADMIN> ~]$ tos status         
[Mar 28 13:42:09]  INFO Checking cluster health status           
TOS Aurora
Tos Version: 24.2 (PRC1.1.0)

System Status: "Ok"
            
Cluster Status:
   Status: "Ok"
   Mode: "Multi Node"

Nodes
  Nodes:
  - ["node1"]
    Type: "Primary"
    Status: "Ok"
    Disk usage:
    - ["/opt"]
      Status: "Ok"
      Usage: 19%
  - ["node3"]
    Type: "Worker Node"
    Status: "Ok"
    Disk usage:
    - ["/opt"]
      Status: "Ok"
      Usage: 4%

registry
  Expiration ETA: 819 days
  Status: "Ok"

Infra
Databases:
- ["cassandra"]
  Status: "Ok"
- ["kafka"]
  Status: "Ok"
- ["mongodb"]
  Status: "Ok"
- ["mongodb_sc"]
  Status: "Ok"
- ["ongDb"]
  Status: "Ok"
- ["postgres"]
  Status: "Ok"
- ["postgres_sc"]
  Status: "Ok"

Application
Application Services Status OK
Running services 50/50

Remote Clusters
Number Of Remote Clusters: 2
  - ["RC"]
     Connectivity Status:: "OK:"
  - ["RC2"]
     Connectivity Status:: "OK"

  Backup Storage:
  Location: "Local
s3:http://minio.default.svc:9000/velerok8s/restic/default "
  Status: "Ok"
  Latest Backup: 2024-03-23 05:00:34 +0000 UTC

Example output for a remote cluster data node:

[<ADMIN> ~]$ tos status         
[Mar 28 13:42:09]  INFO Checking cluster health status           
TOS Aurora
Tos Version: 24.2 (PRC1.0.0)

System Status: "Ok"
            
Cluster Status:
   Status: "Ok"
   Mode: "Single Node"

Nodes
  Nodes:
  - ["node2"]
    Type: "Primary"
    Status: "Ok"
    Disk usage:
    - ["/opt"]
      Status: "Ok"
      Usage: 19%
  
registry
  Expiration ETA: 819 days
  Status: "Ok"

Infra
Databases:
- ["mongodb"]
  Status: "Ok"
- ["postgres"]
  Status: "Ok"

Application
Application Services Status OK
Running services 16/16

  Backup Storage:
  Location: "Local
s3:http://minio.default.svc:9000/velerok8s/restic/default "
  Status: "Ok"
  Latest Backup: 2024-03-23 05:00:34 +0000 UTC