RSP DALQueryError

Support Rubin Science Platform
#1

Hi I’m trying to run some queries on dp1 and I’m getting the error:

DALQueryError: Query Error: Query failed in backend: MERGE_ERROR 2010 (failed to open[/read](https://jrob.nb.data.lsst.cloud/read): http://sdfqserv002.sdf.slac.stanford.edu:44685/6-5771126-0-78967-0.csv, fileSize: 1027353, offset: 0, ex: error: 'Couldn't resolve host name', errnum: 6) 2026-02-10T13:29:01+0000

I noticed this just now whilst trying to rerun queries that were working earlier today. I also tried a tutorial notebook (201.4) and the same error crops up. I presume there’s an issue with the RSP?

#2

Hi James, thanks for reporting this. I can confirm I get the same error message and also that there was an issue with Qserv (TAP backend) last night, and it looks like it’s not resolved yet. We’ll make sure the fix gets reported back here as soon as we confirm the TAP service is restored.

#3

TAP service has been restored. I confirmed it with a simple query on the DP1 object table, and am marking this topic as solved. But as always, please open new Support topics for new issues anytime, thanks!

1 Like
#4

Yes, I can confirm that things are working for me again, cheers!

1 Like
#5

Hi @MelissaGraham looks like the same problem cropped up again for me today (around 14:00 UTC). @solontoi also gets the same error (around 16:30 UTC) so I think it’s not just me!

 DALQueryError: Query Error: Query failed in backend: MERGE_ERROR 2010 (failed to open/read: http://sdfqserv004.sdf.slac.stanford.edu:39953/6-5774874-0-78967-0.csv, fileSize: 1027353, offset: 0, ex:  error: 'Couldn't resolve host name', errnum: 6) 2026-02-11T16:31:47+0000
#6

I can confirm that TAP queries are back up at data.lsst.cloud. It looks like the team caught this earlier today and implemented a fix. Please keep reporting issues as they come up thank you!

#7

Sure thing, queries are working again for me now

#8

Hhm, after a morning of working on some notebooks it’s back down again:

DALQueryError: Query Error: Qserv request failed: operation failed due to: MySqlConnection::getMySql connection is not open.

I see that https://data.lsst.cloud/ has had a red banner all today warning about service disruption so I guess this is ongoing and being actively looked at.

Update: as of 11:40 UTC my queries are running again, service must be intermittent.

#9

Yes the red banner went up once the issue was found to be persistently intermittent (and the fixes temporary). The red banner will stay up until the fix is permanent. Thanks again for keeping up the reporting it’s really useful!