Offline nodes become online after config reload

[nekrolzzy1]

Jenkins and plugins versions report

Environment

Jenkins: 2.504.1
OS: Linux - 6.1.0-31-amd64
Java: 21.0.7 - Oracle Corporation (Java HotSpot™ 64-Bit Server VM)
ace-editor:1.1
ansicolor:1.0.6
ant:513.vde9e7b_a_0da_0f
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apache-httpcomponents-client-4-api:4.5.14-269.vfa_2321039a_83
asm-api:9.8-135.vb_2239d08ee90
bootstrap4-api:4.6.0-6
bootstrap5-api:5.3.5-1
bouncycastle-api:2.30.1.80-256.vf98926042a_9b_
branch-api:2.1217.v43d8b_b_d8b_2c7
build-name-setter:2.5.0
build-timeout:1.38
build-user-vars-plugin:195.v8c35f9d5c3dc
caffeine-api:3.2.0-166.v72a_6d74b_870f
checks-api:370.vb_61a_c57328f3
cloudbees-folder:6.1012.v79a_86a_1ea_c1f
command-launcher:123.v37cfdc92ef67
commons-compress-api:1.27.1-3
commons-lang3-api:3.17.0-87.v5cf526e63b_8b_
commons-text-api:1.13.0-153.v91dcd89e2a_22
conditional-buildstep:1.5.0
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echarts-api:5.6.0-4
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envinject:2.926.v69c9b_3896a_96
envinject-api:1.235.va_14c74f8f487
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gearman-plugin:0.8.0
generic-webhook-trigger:2.3.1
gerrit-trigger:2.42.0
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git-client:6.1.3
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gitlab-oauth:1.22
gradle:2.14.1
gson-api:2.13.1-139.v4569c2ef303f
handlebars:3.0.8
instance-identity:203.v15e81a_1b_7a_38
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jnr-posix-api:3.1.20-138.vdb_9db_a_39182f
job-dsl:1.92
joda-time-api:2.14.0-127.v7d9da_295a_d51
jquery:1.12.4-3
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plain-credentials:195.vb_906e9073dee
plugin-util-api:6.1.0
popper-api:1.16.1-3
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workflow-step-api:700.v6e45cb_a_5a_a_21
workflow-support:968.v8f17397e87b_8
ws-cleanup:0.48

I lost functionality when after jenkins reload (safeRestart/systemctl restart/by jcasc plugin - Reload existing configuration) all previously-set offline agents stay offline. On older jenkins version: Jenkins: 2.346.3 it was work that way. Offline nodes was offline until manual setting it online again. On newer version: Jenkins: 2.504.1 agents all the time(after restart/config reload) becomes online. It is bug or it was a bug before? **Please also take a look Markus comments here:** [Offline nodes become online after config reload](https://community.jenkins.io/t/offline-nodes-become-online-after-config-reload/30907)

What Operating System are you using (both controller, and any agents involved in the problem)?

Debian 12, Java 17/21.

Reproduction steps

1. Turn off node.
2. Reload configuration via casc "reload button"
3. Node become online. - BUG

Expected Results

1. Turn off node.
2. Reload configuration via casc "reload button"
3. Node should be offline after reload.

Actual Results

1. Turn off node.
2. Reload configuration via casc "reload button"
3. Node become online. - BUG

Anything else?

No response