# Routing settings

> Set the default expiry mode for new Projects, require a Project for tieline routes and choose whether every route is persisted as a route request.

Settings → Routing ("Routing") holds a small set of system-wide defaults for how new route requests behave: not per-route or per-connection settings, but the baseline every new Project and route request starts from. Before you begin Access to Settings → Routing (requires project-management permission: the same permission that governs Projects themselves). A Pro or Enterprise license. On a Free or Individual license, the page shows Routing settings are unavailable instead of the settings themselves: this matches the license Projects itself requires. An understanding of Projects , since two of these three settings only matter if you use them. Understand each setting Under Route request defaults : Default expiry mode : the pre-filled Expiry Mode (Prompt for release / Auto-release on expiry) when someone creates a new Project. It's only a starting value, still changeable per-Project at creation, and changing this setting has no effect on Projects that already exist. Require project for tielines : when on, a tieline (cross-router) route request must have a Project attached. See Group and release routes with Projects for what this looks like from the routing side. Persist all routes : when on, every route (not just cross-router tieline routes, which are always persisted) is recorded as a route request. Off by default, since recording every single-router route can add up in a busy facility. Know what changing a setting actually does: and doesn't do None of these settings retroactively touch routes that already exist: Require project for tielines , turned on, doesn't invalidate or break any tieline route that's already live without a Project. It takes effect the next time someone tries to create a new project-less tieline route (rejected before execution), or reroute an existing project-less one (also rejected): not before. Persist all routes , turned off, doesn't immediately delete previously-recorded single-router route requests. Existing entries are cleaned up lazily: the next time a route is taken to that same destination, the stale recorded entry is replaced. Note Buttons doesn't show a confirmation dialog or a "this will affect N routes" preview before saving either setting: there's no built-in safety check here. Consider the effect on live tieline routes and any automation depending on route-request records before changing either one during a production. If you get stuck What you see What to try A tieline route is rejected with a message about needing a project. Require project for tielines is on: assign a Project before taking or rerouting it. An existing tieline route without a Project still seems to be working. That's expected: the requirement only blocks new routes and reroutes, not routes already in place when you turned it on. Single-router routes aren't showing up as route requests. Persist all routes is off by default: turn it on if you need those recorded too. You turned off Persist all routes but old entries are still there. They're cleaned up the next time a route is taken to that destination, not immediately: this is expected. A new Project's Expiry Mode isn't what you expected. Check Default expiry mode here: it's just the starting value, and can still be changed per-Project. Where to go next Group and release routes with Projects Use the routing topology graph