DNS / NTP Server Migration
You can migrate your DNS / NTP server after you have completed your initial deployment of CloudVision. Migrating the DNS / NTP server is typically done if you want to or need to change the DNS / NTP server that CloudVision currently uses.
Migrating the DNS and NTP Server
The process for migrating the DNS / NTP server after the completion of the initial CloudVision installation involves updating the DNS and NTP server entries on each cluster node and modifying the /cvpi/cvp-config.yaml file (on each node) to reflect the updates to the server entries.
Before you begin the migration process, make sure that:
- The IP addresses and hostnames (fqdn) of the nodes must not change.
- For each node, make sure
- At least one DNS server entry is present in the /cvpi/cvp-config.yaml file.
- The DNS server that corresponds to the DNS server entry in the /cvpi/cvp-config.yaml file can be accessed by the cluster throughout the migration process. (The reason for this is that any changes made to resolv.conf take effect immediately upon saving the file.)
- The time difference between the old NTP server and new NTP server should be negligible.
- The old NTP server and new NTP server should be in same time zone.
Complete these steps to migrate the DNS / NTP server.
- On each node, add the new server to /etc/resolv.conf, by adding a new nameserver line at the top of the file. For example, nameserver 172.22.22.40.
- On each node, remove the old server from /etc/resolv.conf, by removing the old nameserver line.
On each node, do the following to update the NTP server:
- Run the ntpstat command to make note of the current NTP server.
- In /etc/ntp.conf, add the new NTP server entry and comment out the entry for the old NTP server.
- Run the service ntpd restart command.
- Run the ntpstat command to verify that the NTP server has been changed on all nodes.
- On each node, edit the /cvpi/cvp-config.yaml file for reflecting changes to the DNS and NTP server entries you made in the previous steps.
To read the /cvpi/cvp-config.yaml file and restart the
network service, run the
/cvpi/tools/cvpConfig.py -y /cvpi/cvp-config.yaml -n nodeXcommand on each node where X is the respective node number.