We are in process of setting up the new es4 and es5 sections, to make es2 and es3 read-only due to space constrains.
We have already set up the servers (T243052), created the wikis and tables (T245720) and added them to etcd (T245806).
Steps pending are: enable them as writable in MW and once we are happy with that step, set es3 to read-only in MW and also on a mysql level (and disconnect replication between them).
es4 is cluster26, and its master is es1020
es5 is cluster27, and its master is es1023
```
root@cumin1001:/home/marostegui# mysql.py -hes1020 enwiki -e "show tables"
+------------------+
| Tables_in_enwiki |
+------------------+
| blobs_cluster26 |
+------------------+
root@cumin1001:/home/marostegui# mysql.py -hes1023 enwiki -e "show tables"
+------------------+
| Tables_in_enwiki |
+------------------+
| blobs_cluster27 |
+------------------+
```
The idea would be to set es4 as writable and once we are ok with it, then follow with es5 to minimize risks.
We are not fully sure what needs to be done apart from the following patch (for es4): https://gerrit.wikimedia.org/r/#/c/operations/mediawiki-config/+/574696/
Can you also let us know if there is a way to actually test this before deploying it everywhere?
Progress:
[x] Enable es4 https://gerrit.wikimedia.org/r/#/c/574696/ https://gerrit.wikimedia.org/r/#/c/operations/mediawiki-config/+/575016/
[] Enable es5
[] Set es2 as read only and disconnect replication https://gerrit.wikimedia.org/r/#/c/operations/mediawiki-config/+/576286/
[] Set es3 as read only and disconnect replication