Topology

Infra, Topology draws the installation: the Meerkat instances serving it, the database they share, and the services the routes point at. It is the first entry of the Infra section, before the routes: what serves, before what is served.

It is at /infra/topology. Root and infra admins only.

The instances

On the left, in the Meerkat frame, every instance running, oldest first:

• its host name - the pod or the container, what you find it by;
• Ready, or why not: what its /readyz answers;
• This node: the instance that answered the screen;
• its version and when it started, in the zone of your profile.

Between two instances, in sync says the change bus keeps them in step: a route, a certificate, a session or the license saved on one reaches the others within a second. Each instance is wired to the database below, the one they share. On the embedded database there is one instance and nothing to keep in sync.

Every instance says who it is every five seconds, whether or not it carries traffic. One that stops says so and leaves the drawing at once; one that goes silent leaves it after twenty seconds.

The services

On the right, Services: one card per address the enabled routes point at, named by the routes that lead there, the address beneath. The icon is web when one of those routes serves pages to people, api otherwise. Only what a route declares is shown: nothing here is discovered.

Each says what the gateway sees of it:

• Answering;
• Not answering, with the reason and since when;
• 1 of 2 ready when the runtime counts its replicas and some are missing;
• Not checked yet for a service no traffic and no check has reached.

The ones that want a look come first, and the list scrolls on its own when there are many. This is a view: a service is changed through its routes, on the Routes screen.

What it warns about

Said in words at the top of the screen, and as a badge on Topology and on Infra in the rail:

• more instances than the license covers, and the time the evaluation notice comes back if they are still that many - a rolling update that ends before then is not an overrun;
• two versions running at once: an update in progress, or one that stopped half way;
• an instance not ready, and why;
• a service not answering.

The screen follows the gateway live: nothing to refresh.