Group by tag failing on one system (working on another)

Hello,
I’m using influxdb version 1.7.10 on CentOS Linux, and have a couple of systems collecting stats data. Recently my graphing of the data lost all the protocol breakout detail. For some reason, “group by” seems to no longer work correctly on the first system and I’m at a loss as to how to debug this

Helper alias

alias iq='influx -database isi_data_insights -execute'

Query showing output with op_name tag and class_name tag

name: cluster.protostats.nfs
time                op_rate            op_name     class_name
----                -------            -------     ----------
1581966179000000000 25.62545585632324  create      create
1581966179000000000 0.9967924952507019 mkdir       create
1581966179000000000 0.2056753188371658 symlink     create
1581966179000000000 18.14943885803223  remove      delete
1581966179000000000 168.0624084472656  access      namespace_read
1581966179000000000 2159.369140625     getattr     namespace_read
1581966179000000000 3226.113037109375  lookup      namespace_read
1581966179000000000 2.460192441940308  readdirplus namespace_read
1581966179000000000 19.40708160400391  rename      namespace_write
1581966179000000000 184.2099151611328  setattr     namespace_write
1581966179000000000 9.09291934967041   commit      other
1581966179000000000 65.9679183959961   statfs      other
1581966179000000000 413.2973327636719  read        read
1581966179000000000 691.9551391601562  write       write
1581966209000000000 27.09298133850098  create      create
1581966209000000000 0.7920569181442261 mkdir       create
1581966209000000000 0.1940261274576187 symlink     create
1581966209000000000 14.13790512084961  remove      delete
1581966209000000000 383.830322265625   access      namespace_read
1581966209000000000 1647.02685546875   getattr     namespace_read
1581966209000000000 3470.64990234375   lookup      namespace_read
1581966209000000000 29.65071868896484  readdirplus namespace_read
1581966209000000000 11.20305633544922  rename      namespace_write
1581966209000000000 277.8653259277344  setattr     namespace_write
1581966209000000000 12.84957313537598  commit      other
1581966209000000000 50.15925979614258  statfs      other
1581966209000000000 440.5131530761719  read        read
1581966209000000000 400.7074279785156  write       write

Attempt to query the average op_rate broken out by op_name and class_name

name: cluster.protostats.nfs
tags: class_name=, op_name=
time                mean
----                ----
1581966180000000000 483.3337546086737
1581966210000000000 433.80888096185834
1581966240000000000

That’s wrong.
On the other system, performing the same query with similar data gets the correct output:

name: cluster.protostats.nfs
tags: class_name=create, op_name=create
time                mean
----                ----
1581965940000000000
1581965970000000000 26.267025629679363
1581966000000000000 29.38319492340088

name: cluster.protostats.nfs
tags: class_name=create, op_name=link
time                mean
----                ----
1581965940000000000
1581965970000000000
1581966000000000000 0.2005978673696518

name: cluster.protostats.nfs
tags: class_name=create, op_name=mkdir
time                mean
----                ----
1581965940000000000
1581965970000000000 1.6038507620493572
1581966000000000000 0.9955756962299349
...

Does anybody have any thoughts as to what I can do to troubleshoot this? I’ve done basic things like making sure I’m not out of space etc. One other key data point, the data on the failing system is being populated using the Python influxdb library, whereas the working system is using the Golang bindings.

Thank you,

Tim

… and it turns out it was my problem.
A dependency changed the data type it was returning for a field so that it flipped from str to unicode which exposed a bug in the collector that flipped the tags into fields.

select *::field on the measurement showed that the tags had now become fields and that was enough to trace back and find the problem.

Thanks,

Tim