[Bug Fix] fix backward compatibility issue in remote tagger dca server

[adel121]

What does this PR do?

Fixes backward compatibility issue in the remote tagger server.

The broken backward compatibility makes it impossible for cluster check runners to get tags using the remote tagger (except for the first runner that connects to the server). This happens if we use older versions of cluster check runners with newer versions of the cluster agent. The backward compatibility was broken in 7.60, but we are fixing it in 7.61 because this feature is disabled by default and has no customer impact since it is not exposed in helm-chart or the operator.

Motivation

Restore backward compatibility.

Describe how you validated your changes

Deploy the cluster agent with CLC runners enabled and using the remote tagger with at least 2 replicas of CLCs.
All CLC replicas should be able to get tags from the cluster tagger.

The CLC runner should have a version 7.59 or older, and the DCA should be using version 7.61 or newer.

Example:

datadog:
  kubelet:
    tlsVerify: false
  clusterChecks:
    enabled: true
  logLevel: DEBUG
  apiKeyExistingSecret: datadog-secret
  appKeyExistingSecret: datadog-secret
  envDict:
    DD_TAGS: "source:node-tags"
    DD_EXTRA_TAGS: "source:node-extra"
    DD_CLUSTER_CHECKS_EXTRA_TAGS: "source:node-cluster_extra" # Note: should never see these
    DD_ORCHESTRATOR_EXPLORER_EXTRA_TAGS: "source:node-orch_extra" # Note: should never see these

clusterChecksRunner:
  replicas: 3
  enabled: true
  image:
    tag: 7.59.0
  envDict:
    DD_CLC_RUNNER_REMOTE_TAGGER_ENABLED: "true"
clusterAgent:
  envDict:
    DD_TAGS: "source:dca-tags"
    DD_EXTRA_TAGS: "source:dca-extra"
    DD_CLUSTER_CHECKS_EXTRA_TAGS: "source:dca-cluster_extra"
    DD_ORCHESTRATOR_EXPLORER_EXTRA_TAGS: "source:dca-orch_extra"
  enabled: true
  replicas: 1

Once everything gets into running state, we should be able to see the same tags in all CLC runner taggers:

kubectl exec datadog-agent-clusterchecks-6bbb898c96-6tfl2 -- agent tagger-list

=== Entity internal://global-entity-id ===
== Source remote =
=Tags: [source:dca-cluster_extra source:dca-extra source:dca-orch_extra source:dca-tags]
===

Without this fix, only one runner will get the tags, and others would fail to get them.

Possible Drawbacks / Trade-offs

Customers who:

• manually enable remote tagger in CLC runners (by setting DD_CLC_RUNNER_REMOTE_TAGGER_ENABLED to true)
• AND upgrade from version 7.59 to 7.60
• AND have at least 2 replicas of clustercheckrunners

Will still be facing broken backward compatibility.

However, we choose not to fix this in 7.60 in order to avoid building a new release candidate and considering that enabling remote tagger in clc runners is disabled by default and not exposed publicly in helm chart or in operator, so it should not have any customer impact (unless the customer manually sets this option).

Additional Notes

[agent-platform-auto-pr]

Test changes on VM

Use this command from test-infra-definitions to manually test this PR changes on a VM:

inv create-vm --pipeline-id=50268562 --os-family=ubuntu

Note: This applies to commit a19ce96

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 98850dd1-2549-4fdb-a260-1e29a1751a78

Baseline: 01c8ef8
Comparison: a19ce96
Diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	tcp_syslog_to_blackhole	ingress throughput	+0.54	[+0.48, +0.60]	1	Logs
➖	basic_py_check	% cpu utilization	+0.46	[-3.35, +4.27]	1	Logs
➖	file_to_blackhole_300ms_latency	egress throughput	+0.21	[-0.43, +0.84]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	+0.19	[-0.60, +0.97]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.13	[-0.76, +1.01]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	+0.07	[-0.68, +0.81]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.02	[-0.07, +0.12]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	+0.00	[-0.01, +0.01]	1	Logs
➖	pycheck_lots_of_tags	% cpu utilization	+0.00	[-3.38, +3.38]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	-0.05	[-0.81, +0.72]	1	Logs
➖	quality_gate_idle	memory utilization	-0.10	[-0.15, -0.06]	1	Logs bounds checks dashboard
➖	quality_gate_idle_all_features	memory utilization	-0.12	[-0.22, -0.02]	1	Logs bounds checks dashboard
➖	otel_to_otel_logs	ingress throughput	-0.15	[-0.85, +0.54]	1	Logs
➖	file_tree	memory utilization	-0.30	[-0.44, -0.15]	1	Logs
➖	file_to_blackhole_1000ms_latency_linear_load	egress throughput	-0.30	[-0.76, +0.16]	1	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	-0.43	[-1.16, +0.30]	1	Logs
➖	quality_gate_logs	% cpu utilization	-1.70	[-4.66, +1.26]	1	Logs

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	file_to_blackhole_0ms_latency	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency_linear_load	memory_usage	10/10
✅	file_to_blackhole_100ms_latency	lost_bytes	10/10
✅	file_to_blackhole_100ms_latency	memory_usage	10/10
✅	file_to_blackhole_300ms_latency	lost_bytes	10/10
✅	file_to_blackhole_300ms_latency	memory_usage	10/10
✅	file_to_blackhole_500ms_latency	lost_bytes	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	quality_gate_idle	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_logs	lost_bytes	10/10
✅	quality_gate_logs	memory_usage	10/10

Explanation

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

CI Pass/Fail Decision

✅ Passed. All Quality Gates passed.

• quality_gate_idle, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.

[adel121]

/merge

[dd-devflow]

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2024-12-03 20:04:14 UTC ℹ️ MergeQueue: pull request added to the queue

The median merge time in main is 22m.