Q: Can I downgrade a NetScaler SD-WAN 4000/5000 appliance to an earlier software release? 

A: A NetScaler SD-WAN 4000/5000 appliance cannot be downgraded to an earlier release. The appliance should have to be factory reset and provisioned again from scratch. 

For example, if an appliance is running: 

Version 7.3.1 it will have the following files for each component: 
SD-WAN 4000/5000 7.3.1-48.418829

• SD-WAN version:                                                         7.3.1-48.418829;
• SVM version:                                                     10.1.120.1105.e;
• NS version:                                                         10.1.129.1105.e;
• XS 6.0 build 50762 with Hotfixes                XS60E001, 003, 010, 014, 018, 020, 023, 024, 026, 028, 029, 031, 033, 034, 035, 037, 39, 40
• Supplemental Pack version                        1.6.2, build 1002

Version 7.2.2 has different files for each SD-WAN, SVM, NS and Supplemental Pack components: 
SD-WAN 4000/5000 7.2.2-24

• SD-WAN version                                                           7.2.2-24;
• SVM version                                                      10.1.124.1353.e;
• NS version                                                          10.1.124.1353.e;
• XS 6.0 build 50762 with Hotfixes                XS60E001, 003, 010, 014, 018, 020, 023, 024, 026, 028, 031
• Supplemental Pack version                         1.6, build 1010

Currently there is no option to downgrade the SVM version (The update software option only applies for the upgrade bundle, not the SVM).

Q: What precaution should be taken while upgrading NetScaler SD-WAN 4000-1000 from version 7.2.2 to version 7.3.4?

A: When upgrading the appliance, if you use the single bundle upgrade (.upg) file then the upgrade gets stuck at step 1/6 and continues to be there unless we go to the CLI and execute a perl command to proceed to next step. 
To resolve this issue:

1. Navigate to cd /var/mps/log and then run
   tail –f bundleupgrade.log

   When you see the following message, proceed to next step:
   Upgrade Status: In progress, doing upgrade.

2. Navigate to cd /var/mps/cb_sb_images/install and run the following command:
   perl upgradebundle.pl –us nsroot –pas <password of SVM>
   You might have to run this command multiple times to get the upgrade done as it involves 6 steps and can hang at any point. 

Q: How can I re-start the setup wizard of a NetScaler SD-WAN VPX appliance?

A: You can remove (set to 0.0.0.0) all hosted IP addresses of NetScaler SD-WAN VPX appliance (both apA and primary IP addresses if it exist)
The following is a sample session:

Login: admin
Password: password
admin> set adapter apa -ip 0.0.0.0 -netmask 0.0.0.0 -gateway 0.0.0.0
admin> set adapter primary -ip 0.0.0.0 -netmask 0.0.0.0 -gateway 0.0.0.0
admin> restart

Q: Why is the upgrade bundle of NetScaler SD-WAN version 7.4.1 displayed as release 7.4.1a?

A: On a previous NetScaler SD-WAN 7.4.0 version there was an issue (#0583172). It was due to a problem with glibc library included in supplemental pack and only occurs during upgrade. System reboot actually fix it. 
NetScaler SD-WAN 7.4.1.a includes a new supplemental pack, rest of others components remains the same.

Q: Why did MAPI application identifier change on NetScaler SD-WAN version 7.3.0 and later? 

A: A default MAPI application identifier rule has been changed from "Port 64999" to "Dynamic TCP" from version 7.3.0 and later. 

Connection to exchange are initiated to End-Point Mapper (EPMAP) service running in port 135, and then the MAPI connections are initiated  to EMSMDB port  (a non-standard port) returned by the EPMAP service. Port was modified to 64999/TCP just to indicate that the EMSMDB port is a non-standard port that is dynamically chosen on every server. 

From version 7.3 onwards, MAPI applications are indicated properly as Dynamic TCP. There is no change/difference in the MAPI acceleration behavior.
Changing back to port 64999 is not be required as the port selection is dynamic.

Q: How can I shutdown a NetScaler SD-WAN appliance remotely via the CLI? 

A:There is no option to shutdown (only restart) a NetScaler SD-WAN appliance remotely via the CLI when logged in as the “admin” user.