topic Re: host name in services running on host dlq in DQL

Host name in services running on host dql

Pablo2 — Fri, 11 Jul 2025 11:08:32 GMT

I have a dql that relates me the services and the hosts on which it is running, but it only gives me the id of the hosts and I would like to have the name of the host instead of the id.

This is the dql:

fetch dt.entity.service
| expand dt.entity.host=runs_on[dt.entity.host]
| fieldsAdd entityAttr(dt.entity.host, "tags")
| filter in(id, classicEntitySelector(concat("type(service), tag(\"APP:", $APPLICATION, "\")")))
| filter in(id, classicEntitySelector(concat("type(service), tag(\"ENVIRONMENT:", $ENTORNO, "\")")))
| dedup id
| fields entity.name, serviceType, entity.customized_name, id, runs_on[dt.entity.host]

I found this in the documentation but I've tried it and it doesn't work for me.

https://docs.dynatrace.com/docs/discover-dynatrace/platform/grail/querying-monitored-entities

Re: host name in services running on host dlq

erh_inetum — Wed, 18 Jun 2025 11:13:27 GMT

Hi Pablo,

Adding this instruction

| lookup sourceField:runs_on[dt.entity.host], lookupField:id, fields:{host.name = entity.name}, [ fetch dt.entity.host ]

you can get the hostname instead of the hostid.

Try to change the DQL adding this line. Somethig like this maybe:

fetch dt.entity.service
| expand dt.entity.host=runs_on[dt.entity.host]

| lookup sourceField:runs_on[dt.entity.host], lookupField:id, fields:{host.name = entity.name}, [ fetch dt.entity.host ]
| fieldsAdd entityAttr(dt.entity.host, "tags")
| filter in(id, classicEntitySelector(concat("type(service), tag(\"APP:", $APPLICATION, "\")")))
| filter in(id, classicEntitySelector(concat("type(service), tag(\"ENVIRONMENT:", $ENTORNO, "\")")))
| dedup id
| fields entity.name, serviceType, entity.customized_name, id, runs_on[dt.entity.host]

and check if you get the desired results.

Hope it helps.

Regards,

Elena.

Re: host name in services running on host dlq

Pablo2 — Wed, 18 Jun 2025 13:00:17 GMT

I always get an empty field in host.name results, it doesnt work for me

Re: host name in services running on host dlq

marco_irmer — Thu, 19 Jun 2025 22:07:52 GMT

You can use the entityName() function in place of the lookup function to get the host names. The other thing to account for is that the runs_on[dt.entity.host] field is an Array field. This means we need to expand the array before we use the entityName function. We can then summarize to form an array of host names. The DQL for this looks as follows:

fetch dt.entity.service | expand dt.entity.host=runs_on[dt.entity.host] | fieldsAdd host_name = entityName(dt.entity.host) // Add the host name | summarize host_names = collectArray(host_name), by:{id,entity.name} // summarize to create a host_names array | fieldsAdd entityAttr(dt.entity.host, "tags") | filter in(id, classicEntitySelector(concat("type(service), tag(\"APP:", $APPLICATION, "\")"))) | filter in(id, classicEntitySelector(concat("type(service), tag(\"ENVIRONMENT:", $ENTORNO, "\")"))) // removed dedup command, as it is no longer needed after using the summarize command above

This should work, I hope.

Re: host name in services running on host dlq

Peter_Youssef — Thu, 03 Jul 2025 14:56:21 GMT

Hello @marco_irmer

Thanks for your inputs, I've tried the suggested DQL Query but it didn't work, what might be the missing part.

fetch dt.entity.service
| expand dt.entity.host=runs_on[dt.entity.host]
| fieldsAdd host_name = entityName(dt.entity.host) // Add the host name
| summarize host_name = collectArray(host_name), by:{id,entity.name} // summarize to create a host_names array
| fieldsAdd entityAttr(dt.entity.host, "tags")
| filter in(id, classicEntitySelector(concat("type(service), tag(\"Env:" , abc", \")")))
| filter in(id, classicEntitySelector(concat("type(service), tag(\"Env:" , xyz", \")")))

BR,

Peter

Re: host name in services running on host dlq

CharlesPerez — Fri, 11 Jul 2025 03:02:38 GMT

Hi @Peter_Youssef,

Try adding this:

| fieldsAdd dt.entity.host.name = entityAttr(dt.entity.host, "entity.name")

Regards,
Charles

Re: host name in services running on host dlq

Peter_Youssef — Tue, 15 Jul 2025 11:19:07 GMT

Thanks @CharlesPerez
will try it out.

Re: Host name in services running on host dql

StrangerThing — Tue, 15 Jul 2025 14:01:21 GMT

Just change your last line with the fields command to this:

| fields entity.name, serviceType, entity.customized_name, id, entityName(dt.entity.host)