Auto-commit: 2025-10-31 08:59:02

Interact/Reg-Filter-Even-Numbered-hostnames/readme.md

@@ -0,0 +1,41 @@
+# 🔍 Regex Filter for Even-Numbered Hostnames
+
+This regex is used in **Tanium filters** to match hostnames ending with an **even digit** in their first label.
+
+---
+
+## ✅ Even-Numbered Hostnames (FQDN)
+
+```regex
+^[^.]*[02468]\..+
+```
+^[^.]* → matches the first label (hostname part before the first dot).
+[02468] → requires it to end with an even digit.
+\..+ → ensures there is a domain suffix (must be a FQDN).
+
+Examples
+- pc100.dkcorp.net ✅
+- pc8.lab.example.org ✅
+- pc101.sud.dkcorp.net ❌ (ends with odd digit 1)
+- pc8 ❌ (not a FQDN, no dot)
+
+## ✅ Even-Numbered Hostnames (Optional FQDN)
+
+```regex
+^[^.]*[02468](?:\..+)?$
+```
+^[^.]* → matches the first label (hostname part before the first dot).
+[02468] → requires it to end with an even digit.
+(?:\..+)? → optional dot + domain (accepts both hostname and FQDN)
+
+✅ Examples
+Matches:
+- pc8
+- pc100
+- pc8.lab
+- pc100.dkcorp.net
+
+❌ Does not match:
+- pc101 (ends with odd digit)
+- pc8. (nothing after the dot)
+- pc.8 (even digit not at the end of first label)