Prior to rediscovering a device, I changed an element’s MTF via command line or DCI rule. After the rediscovery, I see that the MTF has reverted to the original MTF prior to the manual change. Why is this happening?
All supported platforms
eHealth 22.214.171.124X through 6.3.2.XX
ATTENTION: Modification of the mtfMigration.rules file mentioned below is highly not recommended as one change may cast wide spread issues with discoveries of other devices.
The MTF is reverted due to the $NH_HOME/poller/mtfMigration.rules file. There are complicated coding and usage of the mtfMigration.rules which are beyond the scope of this article and should be another indication that one should not modify the file in any way.
In the file, you will see a rule that follows the structure below:
Element LEOJU04-VM66907-SH is discovered with host-resources-nt-server.mtf. However, for reporting purposes, my team needs to use MTF host-resources-nt-server-vmem.mtf.
-Before the MTF change. Checking the assigned MTF file.
$NH_HOME/bin/sys/nhisql "select name,mtf_name from nh_element where name = 'LEOJU04-VM66907-SH'"
-Manually changing the MTF to host-resources-nt-server-vmem.mtf
nhListElements -where "name matches LEOJU04-VM66907-SH" | nhModifyElements -fieldName mibTranslationFile -value host-resources-nt-server-vmem.mtf
-Checking the MTF after the change.
$NH_HOME/bin/sys/nhisql "select name,mtf_name,discover_mtf from nh_element where name = 'LEOJU04-VM66907-SH'"
-Checking the $NH_HOME/poller/mtfMigration.rules file for a rule fitting the format of
-The following rule is found:
Since the rule exists, rediscovery results will show updated elements for those elements which you manually changed the MTF fitting the above scenario.
At this time, there is no further explanation as to why this behavior occurs. Writing DCI rules to change the MTF during discovery/rediscovery may result in duplicate elements. If the new MTF is absolutely necessary, consider opening a ticket with support and requesting a recertification of the device and specify the need for the MTF change.