Discovery renaming servers and changing IPs in unpredictable ways

[priyajames]

Hi,

I am facing issues where it appears that Discovery is renaming servers probably because it is configured to coalesce on a variable other than hostname.

It appears that Discovery is configured to look at Serial Number and this NOT supposed to happen. In this case there are also two CIs with the same name causing a conflict,

Discovery is configured to look for matching serial numbers on a host in addition to hostname. It's only supposed to be matching on hostname

Can you please help me as to how I should reconfigure it ?

Thank You,

Priya

[mamann]

Discovery uses "Identifiers" to help coalesce or match to an existing CI in the CMDB.

You can go to Discovery Definition -> Identifiers to see the list. Discovery will go down the list of each one that is active AND where the CI is in (or will be in) the table in the Applies To field (or a table extended from that one) until it either finds a match, doesn't find a match or exits out.

You can change the order of the identifiers and turn them on/off in order to meet your needs.

Most time however, it is best to match based on serial because it's "unlikely" it will be reused and should be unique.

You can read more about identifiers at http://wiki.servicenow.com/index.php?title=Discovery_Identifiers#gsc.tab=0

[priyajames]

Hi Mark,

This helps but can you tell me as this identifier - "Serial Number & Class Name"is out of the box will there be any discrepancy if I disable this?

The serial number ids not unique here in our case and hence we are having this conflict. I checked the properties and Always update host name is set to "Yes".

Please assist.

Thank You,

Priya

[mamann · Accepted solution]

This could cause problems by turning this off yes.

If you have other devices that do rely on a unique serial number, turning it off could and most likely will cause problems.

There is an article that does cover this which may help.

Discover multiple CIs with the same Serial Number

[priyajames]

These pointers are very helpful Mani. We still haven't figured out a solution yet but will update you once we come to a solution on this.

Thanks much for your help.