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[IMC 5.2] excluding devices from discovery

 
am1sh
Frequent Visitor

[IMC 5.2] excluding devices from discovery

I''ve just upgraded from PCM+ to iMC and I'm having problems with the discovery process.

When auto discovering a subnet, the IMC adds servers, printers and other devices automatically.

This fills the list and very quickly reaches my license limit.

 

How can I exclude certain device categories from beying discovered?

When deleting a device, how can I set it to be excluded from future discovery?

Is there a way, like in PCM+, to perform discovery by LLDP from a given seed device?

 

Thanks.

8 REPLIES 8
LindsayHill
Honored Contributor

Re: [IMC 5.2] excluding devices from discovery

Are you using the Advanced Discovery methods? These give you more control, and let you exclude certain address ranges, etc. You can't exclude specific device types though. Make sure your discovery is not adding non-SNMP devices, and that you're properly restricting your IP ranges and SNMP strings.

 

Do you have any organisation with your IP addressing, or do you have servers, printers, network devices all mixed together?

 

am1sh
Frequent Visitor

Re: [IMC 5.2] excluding devices from discovery

Thanks for your answer.

The problem is that the network devices are on the same IP range as other devices.

And also, many of my other devices have SNMP configured for monitoring them with other products. So excluding SNMP-enabled devices is useless.

LindsayHill
Honored Contributor

Re: [IMC 5.2] excluding devices from discovery

There's no easy answers for you then unfortunately.

Here's what I'd do in your situation:
* Run discovery. Limit your address ranges as much as possible - e.g. exclude DHCP ranges. Do this as an ad-hoc discovery, not scheduled. Do this with one smaller part of your network at first.
* Accept that you'll get extra devices - just go and manually delete them.
* Rinse and repeat, each time running a manual discovery on a different part of your network.
* In future, develop some sort of network design + IP addressing plan that separates network device management VLANs from servers + printers. Or at least use a specific part of the subnet for network gear - e.g. x.x.x.220-254 is just for network gear.
* I would also not rely on auto-discovery in future - just manually add devices to IMC when you add them to your network. This obviously depends on your rate of change, but I'm guessing it's fairly low if you were previously using PCM+, and don't already have any structure to your IP addressing.

Another option is to just import a CSV list of devices, if you are maintaining that (or have a way to export a list from another system, e.g. PCM+).
am1sh
Frequent Visitor

Re: [IMC 5.2] excluding devices from discovery

Thanks.

It's sad that I have to manually add and remove devices.

The main reason I installed PCM+ was to track the changes in the network, because there are many and done by different people.

am1sh
Frequent Visitor

Re: [IMC 5.2] excluding devices from discovery

Does anyone know if the discovery process is changed in v7.0, to allow discovering only devices of a certain type (eg. switches & routers but not printers or servers)?

 

I'm still using PCM+ only because of this feature.

LindsayHill
Honored Contributor

Re: [IMC 5.2] excluding devices from discovery

There are options in 7.0 E0202 for filtering based on device model. You could try those.

 

How many devices do you have, and how many new network devices are added per week?

am1sh
Frequent Visitor

Re: [IMC 5.2] excluding devices from discovery

Hi LindsayHill

 

The filter in auto-discovery has a limit of 50 types per query so I have to manually add every new type of switch I'm adding to the network. If I could just configure it to only add devices of type "Switch"...

 

I have a bout 120 devices. the problem is not that they are added, they move around from one location to another, changing their IP and settings when they do.

This is the reason why I need a network equipment management tool. This is why I purchased PCM. Now the iMC is useless if I need to manually enter every change to the network.

 

I guess I'll use filter with the most common types of switches I use.

LindsayHill
Honored Contributor

Re: [IMC 5.2] excluding devices from discovery

Auto-discovery is going to pick up moved devices as "new", although you'll probably also see some complaints about duplicate systems, duplicate SNMP engine IDs, etc.

That means you'll still have to have some manual intervention, to delete old devices.

Most small-medium networks don't have a huge variety of devices, nor do they have a high rate of change, and lack of addressing structure. That means that your needs are not going to be met by most network management toolsets.

You'll have to figure out what needs are really important to you, and then select the right product for those needs.

If you need complex discovery rules, then something like HP NNMi may be better suited - it has a very powerful discovery engine, with a lot of customisation options, including one to only automatically add devices that are switches or routers. It also has options to automatically delete devices if they are offline for longer than a defined period.