FAQs
HA near-hitless software upgrade
-
What are the prerequisites for the HA near-hitless software upgrade?
The existing customer network must already be running on Citrix SD-WAN 11.1 or higher release which supports the near-hitless upgrade procedure for HA.
-
Is this functionality enabled by default or is there some setting to enable this?
It is enabled by default.
-
What if there are a few sites with Non-HA deployment?
The sites with non-HA deployment are activated at the second step of activation. If the entire network does not have HA deployment then the single step upgrade is activated.
-
What if the activation fails either on the Standby or Active appliance?
The software has a timeout implementation. If the activation on the Standby appliance fails, after the timeout period, activation on the Active appliances is initiated.
-
How long is the timeout period?
The timeout periods for various upgrade activations are:
- Configuration update activation: 5 minutes
- Near hitless software upgrade for HA Step 1: 20 minutes
- Near hitless software upgrade for HA Step 2: 20 minutes
- Single step software upgrade activation: 20 minutes
-
What if Active and Standby are in different software versions because of error/issues during upgrade?
The HA pair continues to work in different software versions. Another Change Management Activation is required to bring the HA pair to the same software version.
-
What if the standby appliance is down when we initiate software upgrade?
The Citrix SD-WAN Orchestrator service waits for the timeout period and then transitions to the second step of the near hitless upgrade activation process.
-
Do we support different software on MCN and branches? This can happen in the case of failures.
The HA pair continues to work in different software versions.
-
Can we time schedule software Upgrade/Activation?
This functionality is not available currently.
-
Does this process apply to RCN based deployments?
Yes.
-
Do we support partial site upgrade?
This functionality is not available currently.
-
Do we support revert-on error functionality?
This functionality is not available currently.
-
How are non-SD-WAN components such as LTE Firmware, SVM, and Citrix Hypervisor Hotfixes upgraded? Can we have scheduled installation of these non-SD-WAN components?
This functionality is not available currently.
-
What if there is any configuration change during the software upgrade? Are we going to inform the user/admin that we are not going to apply the HA near-hitless software upgrade?
Yes. User/Admin is informed that there is a configuration change during current software upgrade activity. The user is given a choice to continue with the normal single step software upgrade procedure, instead of near-hitless upgrade.