Using rollover indexes to reduce shard size?

Hello

Ive been reading up on how to reduce my shard size as it seems my stack has that issue and Ive been reading about rollover indexes but I dont understand them too well....

I have one node.

Im gonna use some real life examples and such so bare with me.

say I have a index right now called

myindex-logons-2021.09

From what I understand, I would have to change that to a sort of "alias index" when my real index would be

myindex-logons-2021.09-001

After I would reach

myindex-logons-2021.09-002

and so on.

I understand that alias index would get the data from *-001 and *-002 but

1: How to I configure this? I imagine I have to use a ILM (I already have one) but Im not sure how to make it a number, make sure my "fake" index is the one I put

2: Deleting indexes; After x days, I would like to delete the "fake" myindex-logons-2021.09 which would force to delete the "real" indexes of myindex-logons-2021.09-001 and myindex-logons-2021.09-002

Is this how it works? Am I saying anything wrong?

Let's start by looking at your existing ILM policies, can you provide the output from GET _ilm/policy.

Sure.

This is what I currently have:

  "ilp-policy" : {
    "version" : 4,
    "modified_date" : "2021-09-01T09:06:02.218Z",
    "policy" : {
      "phases" : {
        "hot" : {
          "min_age" : "0ms",
          "actions" : {
            "set_priority" : {
              "priority" : 100
            }
          }
        },
        "delete" : {
          "min_age" : "210d",
          "actions" : { }
        }
      }
    }
  },

As you can see, currently after 210 days, the indexes get deleted; Im expermenting by changing the indexes to monthly to see if overtime the shard size gets reduced (I had it as daily logs)

Is that the only policy?

Yes it is