MemberOf relationship value missing from the topology for the device

Products

• VMware Smart Assurance
• Network Observability

Issue/Introduction

MemberOf value missing from the Smarts IP domain manager topology for the device

dmctl -s <DOMAIN NAME>get ICIM_UnitaryComputerSystem::<device name>::MemberOf | cat
{ }

Environment

All Supported Smarts releases

Cause

Each discovery system will be in one partition. Partition represents a connected (L2&L3) network.

If a system has no neighbor OR if a system is unsupported or unmanaged it will not be part of any partition and it represents stale piece.

The MemberOf attribute is different for SAM and IP.

• In SAM, the MemberOf attribute represents the domain to which it belongs.
• In the IP domain, the MemberOf attribute represents the partition to which it belongs.

More often than not, network devices managed by InCharge are not connected continuously due to various reasons.
For example:

• Devices are not in the seed file
• Devices are not managed by other management platforms where the initial seeds for discovery are taken from
• Network management systems do not have access to manage the backbone switches and routers that interconnect managed devices

As a result, the managed domain is broken into network partitions. In some scenarios, a failure in the network can break connectivity between the management station and all the devices in a partition.

Support for Partition in the Smarts IP manager adds the diagnosis of Partition Down failure. A Partition Down failure occurs when the management station loses connection to ALL the devices in a partition.

Resolution

External specifications:

A partition is defined as a group of managed computer systems in the Smarts topology that are interconnected to each other, that is, a managed computer system can reach any other managed computer system in the same partition by traversing layer 2 and/or layer 3 connectivity relationships.

New class called Partition in ICIM.
New root cause: Partition Down

ConsistsOf/MemberOf relationships between Partition and ICIM_UnitaryComputerSystem (Switch, Router, Host, etc.)

New computed relationship-set ConnectedSystems in IPNetwork

- show computer systems in a network, similar to ConnectedSystems in a VLAN.

Configuration:
- Enable/disable partitioning through sm_tpmgr and discovery.conf
- Set partition DisplayName through partition.conf file

It is very important to notice that Smarts does not report failures on ANY unmanaged entity. It is thus important to notice the effect of that on partitions.
If two managed devices are connected via two unmanaged interfaces, if the interfaces go down, Smarts will not send any notifications. Users could be mislead to think that because the devices are connected via unmanaged interfaces, that the partition program was going to create two separate partitions.
However, only unmanaged devices cause partition connectivity to break. Unmanaged interfaces do not cause that.