F5 LTM not discovered by Servicenow discovery

Depends on how you're trying to discover. SNMP is how Service-Now's MID server denote a BigIP device.

http://wiki.servicenow.com/index.php?title=Data_Collected_by_Discovery_on_F5_BIG_IPgsc.tab=0

If you're trying to discover the device as you would other SSH systems, it'll come back as a linux box (We're CentOS). Refer here to identify as F5 devices:

https://community.servicenow.com/thread/163223

Disclosure and Service Mapping can find F5 BIG-IP load balancers by means of SNMP, SSH, and through the REST API.
For F5 Global Traffic Manager (GTM) GIB-IP load balancers, Discovery can determine the DNS name of the F5 GTM equipment as well as the DNS names of the relative multitude of servers related with the heap balancer that get disseminated traffic. To see this information, explore to All > Configuration > Load Balancers > LB Hardware and open the F5 load balancer record. Then, at that point, select the DNS Names for CIs related list. Administration Mapping utilizes this data to plan F5 connections.
F5 bunch disclosure
The flat disclosure interaction can find F5 groups. To find bunches, the certifications probably read authorization to traffic gatherings. For SNMP, this is the customary understood authorization. For SSH, you really want to have Traffic Management Shell (TMSH shell) empowered and available.

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