diff --git a/README.md b/README.md
index ca8c2e104..f3c5a3e38 100644
--- a/README.md
+++ b/README.md
@@ -1032,6 +1032,8 @@ Either `present` or `absent`. Defines if the feature `checker` should be enabled
 
 ##### `concurrent_checks`
 The maximum number of concurrent checks. Defaults to `512`.
+Note: deprecated in Icinga 2.11, replaced by global constant
+MaxConcurrentChecks which will be set if you still use concurrent_checks.
 
 #### Class: `icinga2::feature::mainlog`
 Enables or disables the `mainlog` feature.
diff --git a/data/common.yaml b/data/common.yaml
index 33eb28731..3a91b88d9 100644
--- a/data/common.yaml
+++ b/data/common.yaml
@@ -44,6 +44,7 @@ icinga2::globals::reserved:
   - LogNotice
   - LogWarning
   - Math
+  - MaxConcurrentChecks
   - ModAttrPath
   - NodeName
   - OK
diff --git a/manifests/feature/checker.pp b/manifests/feature/checker.pp
index 0aefdbed3..5f8bd30b7 100644
--- a/manifests/feature/checker.pp
+++ b/manifests/feature/checker.pp
@@ -9,6 +9,8 @@
 #
 # [*concurrent_checks*]
 #   The maximum number of concurrent checks. Defaults to 512.
+#   Note: deprecated in Icinga 2.11, replaced by global constant
+#   MaxConcurrentChecks which will be set if you still use concurrent_checks.
 #
 #
 class icinga2::feature::checker(