Help with SNMP Discovery of Citrix NetScaler (SDX/VPX) via ServiceNow Discovery

praveenkshanmu
Tera Contributor

‎07-24-2025 09:33 AM

Hello All,

 

I'm currently working on setting up SNMP-based Discovery in ServiceNow for our Citrix NetScaler environment. We have a mix of SDX appliances hosting multiple VPX instances, and I want to understand the best way to approach this using ServiceNow Discovery.

My goal is to:

  1. Discover the SDX appliances first.

  2. Then discover the VPX instances hosted within the SDX.

  3. Finally, identify and map the VIPs configured on the VPX instances.

A few questions:

  • Is there any documentation on how SNMP Credentials should be setup or what privileges it needs ?

  • Do I need different credentials for SDX and VPX discovery, or can one set of credentials work for all?

  • Does Discovery natively differentiate between SDX and VPX, or are there best practices for setting up classification and identification rules?

  • Any known MIBs or OIDs that should be enabled or exposed for SNMP polling of these devices?

Any guidance, examples, or success stories would be really appreciated!

 

Thank you,

Praveen

0 Helpfuls
  • 430 Views
1 REPLY 1

AJ-TechTrek
Giga Sage
Giga Sage

‎07-27-2025 07:53 AM

Hi @praveenkshanmu ,

 

As per my understanding goal is :-


1 Discover SDX appliances


2 Discover VPX instances hosted within SDX


3 Identify & map VIPs configured on VPX


All are discoverable via SNMP, provided correct credentials, MIBs, and Discovery configuration.

 

1. SNMP credentials setup & privileges
* SNMP v2c: needs community string (usually “readonly”).
* SNMP v3: needs:
* Auth protocol + password
* Privacy protocol + password
* Security level (authPriv recommended)
Privileges:
* Read-only is usually enough.
* But you must ensure the SNMP user can read:
* System info: model, hostname, serial
* Interface tables
* Citrix NetScaler MIBs for VIPs and vServers
If the SDX or VPX SNMP config is limited by ACL or vdom context, Discovery will not see all objects.

 

2. Do I need different credentials for SDX and VPX?
* Usually: Yes
* SDX: has its own management plane & SNMP daemon
* Each VPX: is a separate VM, each with its own SNMP daemon & config
* So: create:
* Credential for SDX (e.g., “SDX-SNMP”)
* Credential(s) for VPX (can reuse same if same community string, but separate targets)

 

3. Does Discovery natively differentiate SDX vs VPX?
* By default, Discovery classifies based on SNMP sysDescr, sysObjectID, and model name.
* SDX and VPX have different sysObjectIDs / sysDescr.
* Best practices:
* Review / adjust the SNMP classifier (on CI Class Manager → IP Switch / Network Gear / Load Balancer classes).
* Map SDX → cmdb_ci_netdevice / Load balancer / custom SDX table
* VPX → cmdb_ci_lb_virtual / cmdb_ci_lb_instance (depending on model)
* Identification rules:
* SDX: serial + hostname
* VPX: serial (if available) + hostname or management IP

 

4. VIP discovery (vServers)
* VIPs configured on VPX can be discovered via SNMP:
* Use Citrix NetScaler MIBs:
* NS-VPN-MIB
* NS-SSL-MIB
* NS-AG-MIB
* NS-LB-MIB → especially nsLbVServerTable
* Ensure these MIBs are loaded & accessible on the MID Server if you plan to build custom SNMP probes/patterns.
* ServiceNow OOB usually discovers virtual servers as cmdb_ci_lb_virtual.

 

5. Documentation & resources
* Official guide:
ServiceNow® Discovery SNMP Classifiers & Credentials
* Citrix MIBs download:
Citrix ADC MIBs
* Community best practices:
* Review custom SNMP probes to get specific VIP tables.
* Use Pattern Designer to extend Discovery for VPX VIPs if needed.

 

6. Recommended process summary:
1. Discover SDX first (management IP, SNMP).
2. Discover VPX:
* Target VPX management IPs (each must have SNMP enabled).
3. Adjust classifier rules (sysObjectID / sysDescr).
4. Verify Discovery finds:
* SDX as hardware appliance
* VPX as virtual appliances (load balancers)
* VIPs as cmdb_ci_lb_virtual
5. Validate relationships:
* SDX “hosts” VPX
* VPX “has” VIPs

 

7. Known tips
* SDX can expose VPX info via its management SNMP, but often limited.
* Better to discover VPX directly.
* Confirm SNMP reachability:
* MID Server ↔ SDX
* MID Server ↔ VPX (management IPs)
* Use Discovery Debug Logs to check classifier matches.

 

Please appreciate the efforts of community contributors by marking appropriate response as Mark my Answer Helpful or Accept Solution this may help other community users to follow correct solution in future.
 
Thank You
AJ - TechTrek with AJ
LinkedIn:- https://www.linkedin.com/in/ajay-kumar-66a91385/
YouTube:- https://www.youtube.com/@learnitomwithaj
ServiceNow Community MVP 2025

0 Helpfuls