routeros-scripting

RouterOS Scripting & CLI Config

RouterOS scripts (.rsc, /system/script, scheduler on-event, Netwatch hooks, and interactive CLI snippets) use RouterOS's own language. It is not shell, Lua, Python, or Tcl. For the syntax baseline, see references/syntax.md. This skill focuses on the traps that LLMs are likely to confidently get wrong.

Do Not Use Interactive Row Numbers in Scripts

Interactive print output shows temporary row numbers (0, 1, 2...) for the current console buffer. They are not stable object IDs and are not usable inside scripts.

# WRONG in scripts — "1" is only an interactive print-buffer row number
/ip/route/set 1 gateway=3.3.3.3

# Better — internal IDs have a * prefix, but can change if objects are removed/re-added
/ip/route/set *1 gateway=3.3.3.3

# Best — resolve the target at runtime
/ip/route/set [find dst-address="0.0.0.0/0"] gateway=3.3.3.3

For generated config, use stable selectors such as comment=, name=, or a unique address/list value. Internal IDs are visible in print as-value as .id=*HEX.

Treat [find] Results as ID Arrays

[find ...] returns zero, one, or many internal IDs. Many commands accept that array directly (set, remove, disable), but code that needs exactly one object should check the count before get.

:local ids [/interface/find where name="ether1"]
:if ([:len $ids] = 1) do={
  :put [/interface/get ($ids->0) name]
} else={
  :error ("expected exactly one interface, got " . [:len $ids])
}

Use [find comment="my-tool-tag"] for idempotent cleanup, not broad selectors such as [find dynamic=no] that can delete unrelated user configuration.

Quote IP Prefixes in find / where

RouterOS does aggressive type conversion, but not always in the direction you expect. For /ip/address, the address property is stored as a string including the prefix length. An unquoted literal like 111.111.1.1/24 is an IP-prefix value and may match nothing.