What ACC-V cannot do that Horizontal Discovery does?

[Suggy]

My customer doesnt want to give us the credentials for Discovery project.

They are asking to use ACC for discovering the CIs

I want to know the list of all limitations and gaps with ACC-V when compared to Horizontal Discovery (HD)

1. Regarding attributes - can ACC-V discover each and every attribute that HD does?

2. Relationships?

3. IRE?

4. Any other points?

thanks in advance!!!

[AJ-TechTrek · Accepted solution]

Hi @Suggy 

Quick context as per my understanding

* Horizontal Discovery (HD): MID Server‑based, credential‑based, active discovery.
* ACC‑V: Agent‑based (ServiceNow Agent Client Collector ‑ Visibility), uses installed agents; credential‑less from ServiceNow side.

1. Attributes coverage
ACC‑V can collect a lot of host data (CPU, RAM, disk, OS, NICs, installed software).
But:
* ACC‑V does NOT collect everything HD can.
* Some attributes HD collects (e.g., specific hardware inventory, BIOS info, deep hypervisor/cluster details, some storage attributes) may not be fully collected by ACC‑V.
* ACC‑V mainly focuses on:
* cmdb_ci_computer & child tables (Windows, Unix)
* cmdb_ci_network_adapter, disks, interfaces
* Software installations & usage
* Complex devices: storage arrays, network gear, load balancers etc. → ACC‑V doesn’t discover these. HD does, via SNMP / API.
So if you rely on full hardware model info, firmware, power supply, blade chassis info, etc → HD is required.

2. Relationships
* ACC‑V collects limited relationship data:
* e.g., Runs on::Runs between OS & hypervisor (if supported)
* Host → installed software
* Does NOT discover:
* Network topology
* Cluster membership
* Load balancer → pool membership
* Storage → volume relationships
* Server → application service maps
* HD (with patterns & probes) discovers complex, dynamic relationships by following connections, ports, APIs.
So, service mapping & full topologies need HD.

3. IRE (Identification & Reconciliation Engine)
* Both ACC‑V and HD use IRE to write into CMDB.
* ACC‑V generates payload → IRE runs to match / insert.
* Difference: data completeness.
* If ACC‑V doesn’t collect enough identifiers (e.g., missing serial number / BIOS UUID / hostname), you can get more duplicates.
* With HD, you usually have better identifier data (serials, UUIDs, etc).

4. Other Points and Limitations

Area	ACC‑V	HD
Agent deployment	Needs agent installed & managed	No agent needed
Coverage	Only OS-level CIs (servers, some software)	All infra & cloud (network, storage, databases, cloud native)
Discovery types	Snapshot only	Snapshot + change tracking
Cloud discovery	ACC‑V can't discover cloud services & native resources	HD supports Cloud API discovery
Real-time	ACC‑V can be near real‑time	HD is scheduled
Dependency maps	Limited	Full Service Mapping patterns
Custom patterns	Not supported	Fully supported
Serverless / credential-less	ACC‑V yes	HD needs credentials (or cloud tokens)

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Thank You
AJ - TechTrek with AJ
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ServiceNow Community MVP 2025

[Gomathi Kannan]

Hi @AJ-TechTrek ,

This is really helpful. Can you please confirm whether we will be able to discover the Network devices(Switch, Load Balancer, Router) and VCenter (ESX server) using ACC - V?

Thanks and Regards,

Gomathi K

[AJ-TechTrek]

Hi @Gomathi Kannan ,

As per my understanding , ServiceNow ACC‑V can only discover what’s installed on the OS where the ACC agent itself is running.


This means:
* ACC‑V is designed to discover host-level (OS-level) CIs like:
* Servers (Windows, Linux)
* Installed applications
* Running processes
* File system data
* Local agents, etc.

ACC‑V cannot discover:
* Network devices like:
* Switches
* Routers
* Firewalls
* Load balancers
Because these do not run an OS where the ACC agent can be installed.
* vCenter / ESX hosts themselves (from the hypervisor or Virtual layer)

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 - ITOM Trainer
LinkedIn:- https://www.linkedin.com/in/ajay-kumar-66a91385/
YouTube:- https://www.youtube.com/@learnitomwithaj
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ServiceNow Community MVP 2025