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+# check_gpg_key_expiration.sh
+
+A check script for icinga2 to check for the expiration of GPG keys (local or online).
+
+    Check gpg expiration date. Arguments:
+    --url URL: Where to find the GPG key. Path to a local file or an URL to download from.
+    --warn DAYS: Warning threshold (integer in days)
+    --crit DAYS: Critical threshold (integer in days)