Hello support team,

I recently patched our Jenkins servers and Jenkins got upgraded from  2.332.3 to 2.346.2. After the upgrade, all agents went offline. After some investigation, I figured none of the agents have the option "launch agent via ssh" which is provided by the ssh-slaves plugin. I tried downgrading Jenkins to its older version but I run into errors. Also, On the newer Jenkins version, there is no way I can downgrade ssh-slave since the only supported version is the latest one. Can you help me understand how can I fix this? 

Here is the Jenkins and plugin details on working Jenkins master vs nonworking Jenkins master. 

Jenkins plugins on non working versions:

• Jenkins: 2.346.2
  OS: Linux - 3.10.0-1160.71.1.el7.x86_64
  —
  ace-editor:1.1
  active-directory:2.25.1
  ant:475.vf34069fef73c
  antisamy-markup-formatter:2.7
  apache-httpcomponents-client-4-api:4.5.13-138.v4e7d9a_7b_a_e61
  artifactory:3.17.0
  authentication-tokens:1.4
  blueocean:1.25.5
  blueocean-autofavorite:1.2.5
  blueocean-bitbucket-pipeline:1.25.5
  blueocean-commons:1.25.5
  blueocean-config:1.25.5
  blueocean-core-js:1.25.5
  blueocean-dashboard:1.25.5
  blueocean-display-url:2.4.1
  blueocean-events:1.25.5
  blueocean-executor-info:1.25.5
  blueocean-git-pipeline:1.25.5
  blueocean-github-pipeline:1.25.5
  blueocean-i18n:1.25.5
  blueocean-jira:1.25.5
  blueocean-jwt:1.25.5
  blueocean-personalization:1.25.5
  blueocean-pipeline-api-impl:1.25.5
  blueocean-pipeline-editor:1.25.5
  blueocean-pipeline-scm-api:1.25.5
  blueocean-rest:1.25.5
  blueocean-rest-impl:1.25.5
  blueocean-web:1.25.5
  bootstrap4-api:4.6.0-5
  bootstrap5-api:5.1.3-7
  bouncycastle-api:2.26
  branch-api:2.1046.v0ca_37783ecc5
  build-pipeline-plugin:1.5.8
  build-timeout:1.21
  built-on-column:1.1
  caffeine-api:2.9.3-65.v6a_47d0f4d1fe
  checks-api:1.7.4
  cloudbees-bitbucket-branch-source:784.v7fcdc7c670f6
  cloudbees-folder:6.740.ve4f4ffa_dea_54
  cobertura:1.17
  code-coverage-api:3.0.4
  command-launcher:84.v4a_97f2027398
  conditional-buildstep:1.4.2
  config-file-provider:3.11.1
  credentials:1139.veb_9579fca_33b_
  credentials-binding:523.vd859a_4b_122e6
  data-tables-api:1.12.1-2
  declarative-pipeline-migration-assistant-api:1.5.2
  display-url-api:2.3.6
  docker-commons:1.19
  docker-workflow:1.29
  durable-task:496.va67c6f9eefa7
  echarts-api:5.3.3-1
  embeddable-build-status:237.v37e2c03964c9
  envinject:2.875.v9b_9e962da_a_ec
  envinject-api:1.199.v3ce31253ed13
  external-monitor-job:192.ve979ca_8b_3ccd
  favorite:2.4.1
  font-awesome-api:6.1.1-1
  forensics-api:1.15.1
  git:4.11.4
  git-client:3.11.1
  git-server:1.11
  github:1.34.5
  github-api:1.303-400.v35c2d8258028
  github-branch-source:1677.v731f745ea_0cf
  github-organization-folder:1.6
  gradle:1.39.4
  handlebars:3.0.8
  handy-uri-templates-2-api:2.1.8-22.v77d5b_75e6953
  htmlpublisher:1.30
  http_request:1.16
  ivy:2.2
  jackson2-api:2.13.3-285.vc03c0256d517
  jakarta-activation-api:2.0.1-1
  jakarta-mail-api:2.0.0-6
  javadoc:217.v905b_86277a_2a_
  javax-activation-api:1.2.0-4
  javax-mail-api:1.6.2-7
  jaxb:2.3.6-1
  jdk-tool:55.v1b_32b_6ca_f9ca
  jenkins-design-language:1.25.5
  jenkins-multijob-plugin:611.v9d3180d752e6
  jira:3.7.1
  jjwt-api:0.11.5-77.v646c772fddb_0
  jquery:1.12.4-1
  jquery-detached:1.2.1
  jquery3-api:3.6.0-4
  jsch:0.1.55.61.va_e9ee26616e7
  junit:1119.1121.vc43d0fc45561
  ldap:2.11
  lockable-resources:2.16
  mailer:435.v79ef3972b_5c7
  matrix-auth:3.1.5
  matrix-project:772.v494f19991984
  maven-plugin:3.19
  mercurial:2.16.2
  mina-sshd-api-common:2.8.0-36.v8e25ce90d4b_1
  mina-sshd-api-core:2.8.0-36.v8e25ce90d4b_1
  momentjs:1.1.1
  okhttp-api:4.9.3-108.v0feda04578cf
  pam-auth:1.8
  parameterized-trigger:2.45
  pipeline-build-step:2.18
  pipeline-github-lib:38.v445716ea_edda_
  pipeline-graph-analysis:195.v5812d95a_a_2f9
  pipeline-groovy-lib:612.v84da_9c54906d
  pipeline-input-step:449.v77f0e8b_845c4
  pipeline-milestone-step:101.vd572fef9d926
  pipeline-model-api:2.2114.v2654ca_721309
  pipeline-model-declarative-agent:1.1.1
  pipeline-model-definition:2.2114.v2654ca_721309
  pipeline-model-extensions:2.2114.v2654ca_721309
  pipeline-rest-api:2.24
  pipeline-stage-step:293.v200037eefcd5
  pipeline-stage-tags-metadata:2.2114.v2654ca_721309
  pipeline-stage-view:2.24
  plain-credentials:139.ved2b_9cf7587b
  plugin-util-api:2.17.0
  popper-api:1.16.1-3
  popper2-api:2.11.5-2
  prism-api:1.28.0-2
  pubsub-light:1.16
  rbenv:0.0.17
  rebuild:1.34
  resource-disposer:0.19
  ruby-runtime:0.12
  run-condition:1.5
  saltstack:3.2.2
  scm-api:620.v0a_5b_1f8054c0
  script-security:1175.v4b_d517d6db_f0
  slack:616.v03b_1e98d13dd
  snakeyaml-api:1.30.2-76.vc104f7ce9870
  snow:1.1.2
  sse-gateway:1.25
  ssh-credentials:295.vced876c18eb_4
  ssh-slaves:1.834.v622da_57f702c
  sshd:3.242.va_db_9da_b_26a_c3
  structs:324.va_f5d6774f3a_d
  timestamper:1.18
  token-macro:308.v4f2b_ed62b_b_16
  trilead-api:1.71.v9e7860a_67a_df
  variant:59.vf075fe829ccb
  versionnumber:1.9
  windows-slaves:1.8.1
  workflow-aggregator:590.v6a_d052e5a_a_b_5
  workflow-api:1188.v0016b_4f29881
  workflow-basic-steps:986.v6b_9c830a_6b_37
  workflow-cps:2759.v87459c4eea_ca_
  workflow-cps-global-lib:588.v576c103a_ff86
  workflow-durable-task-step:1199.v02b_9244f8064
  workflow-job:1207.ve6191ff089f8
  workflow-multibranch:716.vc692a_e52371b_
  workflow-scm-step:400.v6b_89a_1317c9a_
  workflow-step-api:639.v6eca_cd8c04a_a_
  workflow-support:838.va_3a_087b_4055b
  ws-cleanup:0.42
  yum:1.0-4-SNAPSHOT (private-b1edd433-jenkins)

Jenkins plugins on working servers:

• Jenkins: 2.332.3
  OS: Linux - 3.10.0-1160.66.1.el7.x86_64
  —
  ace-editor:1.1
  active-directory:2.25.1
  ansicolor:1.0.1
  ant:1.13
  antisamy-markup-formatter:2.7
  apache-httpcomponents-client-4-api:4.5.13-1.0
  artifactory:3.16.2
  authentication-tokens:1.4
  aws-credentials:1.32
  aws-java-sdk:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-cloudformation:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-codebuild:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-ec2:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-ecr:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-ecs:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-elasticbeanstalk:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-iam:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-logs:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-minimal:1.12.101-300.vc09c7be9cb57
  aws-java-sdk-ssm:1.12.101-300.vc09c7be9cb57
  bootstrap4-api:4.6.0-3
  bootstrap5-api:5.1.3-3
  bouncycastle-api:2.25
  branch-api:2.1046.v0ca_37783ecc5
  build-pipeline-plugin:1.5.8
  build-timeout:1.20
  built-on-column:1.1
  caffeine-api:2.9.2-29.v717aac953ff3
  checks-api:1.7.2
  cloudbees-folder:6.722.v8165b_a_cf25e9
  cobertura:1.17
  code-coverage-api:2.0.4
  command-launcher:1.6
  conditional-buildstep:1.4.2
  config-file-provider:3.8.2
  credentials:2.6.1.1
  credentials-binding:1.27.1
  data-tables-api:1.11.3-4
  display-url-api:2.3.5
  docker-commons:1.17
  docker-workflow:1.26
  durable-task:496.va67c6f9eefa7
  echarts-api:5.2.2-1
  envinject:2.4.0
  envinject-api:1.8
  external-monitor-job:1.7
  font-awesome-api:5.15.4-3
  forensics-api:1.7.0
  git:4.11.3
  git-client:3.11.0
  git-server:1.10
  github:1.34.1
  github-api:1.301-378.v9807bd746da5
  github-branch-source:2.11.4
  github-organization-folder:1.6
  gradle:1.38
  handlebars:3.0.8
  http_request:1.15
  ivy:2.1
  jackson2-api:2.13.3-285.vc03c0256d517
  javadoc:1.6
  javax-activation-api:1.2.0-3
  javax-mail-api:1.6.2-5
  jaxb:2.3.6-1
  jdk-tool:1.5
  jenkins-multijob-plugin:1.36
  jjwt-api:0.11.2-9.c8b45b8bb173
  jquery:1.12.4-1
  jquery-detached:1.2.1
  jquery3-api:3.6.0-2
  jsch:0.1.55.2
  junit:1.53
  ldap:2.7
  lockable-resources:2.12
  mailer:414.vcc4c33714601
  matrix-auth:3.1.2
  matrix-project:771.v574584b_39e60
  maven-plugin:3.16
  momentjs:1.1.1
  okhttp-api:4.9.3-105.vb96869f8ac3a
  pam-auth:1.6.1
  parameterized-trigger:2.44
  pipeline-build-step:2.18
  pipeline-github-lib:38.v445716ea_edda_
  pipeline-graph-analysis:1.12
  pipeline-groovy-lib:591.v3a_7f422b_d058
  pipeline-input-step:448.v37cea_9a_10a_70
  pipeline-milestone-step:101.vd572fef9d926
  pipeline-model-api:1.9.3
  pipeline-model-declarative-agent:1.1.1
  pipeline-model-definition:1.9.3
  pipeline-model-extensions:1.9.3
  pipeline-rest-api:2.19
  pipeline-stage-step:293.v200037eefcd5
  pipeline-stage-tags-metadata:1.9.3
  pipeline-stage-view:2.19
  plain-credentials:1.7
  plugin-util-api:2.5.1
  popper-api:1.16.1-2
  popper2-api:2.10.2-1
  rbenv:0.0.17
  rebuild:1.32
  resource-disposer:0.16
  ruby-runtime:0.12
  run-condition:1.5
  saltstack:3.2.2
  scm-api:608.vfa_f971c5a_a_e9
  script-security:1138.v8e727069a_025
  slack:608.v19e3b_44b_b_9ff
  snakeyaml-api:1.29.1
  snow:1.1.2
  ssh-credentials:1.19
  ssh-slaves:1.806.v2253cedd3295
  sshd:3.1.0
  structs:318.va_f3ccb_729b_71
  timestamper:1.17
  token-macro:293.v283932a_0a_b_49
  trilead-api:1.0.13
  variant:1.4
  versionnumber:1.9
  windows-slaves:1.8
  workflow-aggregator:581.v0c46fa_697ffd
  workflow-api:1153.vb_912c0e47fb_a_
  workflow-basic-steps:2.24
  workflow-cps:2660.vb_c0412dc4e6d
  workflow-cps-global-lib:548.v9085a486966a
  workflow-durable-task-step:1139.v252a_e12e8463
  workflow-job:1145.v7f2433caa07f
  workflow-multibranch:716.vc692a_e52371b_
  workflow-scm-step:2.13
  workflow-step-api:625.vd896b_f445a_f8
  workflow-support:813.vb_d7c3d2984a_0
  ws-cleanup:0.42
  yum:1.0-4-SNAPSHOT (private-b1edd433-jenkins)

Not related: I tried disabling all plugins listed here to see if this resolves the issue but it did not help.