add doc/rotate-ntp.md

1 files changed, 40 insertions, 0 deletions

diff --git a/doc/rotate-ntp.md b/doc/rotate-ntp.md
new file mode 100644
index 0000000..eb04f5c
--- /dev/null
+++ b/doc/rotate-ntp.md
@@ -0,0 +1,40 @@
+Rotate NTP servers
+==================
+
+[◀ Go back to main README](../README.md)
+
+Description
+-----------
+
+RouterOS requires NTP servers to be configured by IP address. Servers from a
+pool may appear and disappear, leaving broken NTP configuration.
+
+This script allows to rotate IP addresses from a given pool.
+
+Requirements and installation
+-----------------------------
+
+Just install the script:
+
+    $ScriptInstallUpdate rotate-ntp;
+
+Configuration
+-------------
+
+The configuration goes to `global-config-overlay`, this is the parameter:
+
+* `NtpPool`: dns name of ntp server pool
+
+Usage and invocation
+--------------------
+
+Just run the script to update the NTP configuration with actual IP
+addresses from pool if required.
+
+Alternatively a scheduler can be created:
+
+    / system scheduler add interval=5d name=rotate-ntp on-event="/ system script run rotate-ntp;" start-time=startup;
+
+---
+[◀ Go back to main README](../README.md)  
+[▲ Go back to top](#top)