# Disabling High Availability To disable High Availability, all leaves in availability group 2 need to be deleted and either removed from the cluster or re-added into availability group 1. ## Before You Start If the cluster is configured with `leaf_failover_fanout` set to `load_balanced`, change it to `paired` before removing the leaves: ```sql SHOW VARIABLES LIKE '%fanout%'; ``` ```output +--------------------------------------+ | Variable_name | Value | +--------------------------------------+ | leaf_failover_fanout | load_balanced | ---------------------------------------+ 1 row in set (0.00 sec) ``` ```sql SET GLOBAL leaf_failover_fanout='paired'; ``` ```output Query OK, 0 rows affected (0.01 sec) ``` ## Step 1. Remove all leaves in availability group 2 Connect to SingleStore on the master aggregator and list the leaves to find the ones in availability group 2. ```shell sdb-admin list-nodes -r leaf ``` ```output +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | MemSQL ID | Role | Host | Port | Process State | Connectable? | Version | Recovery State | Availability Group | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | 4DAE7D1F54 | Leaf | node1 | 3310 | Running | True | 6.7.7 | Recovering | 2 | | 52CA34CD0C | Leaf | node1 | 3311 | Running | True | 6.7.7 | Online | 2 | | 74BBE83C45 | Leaf | node1 | 3308 | Running | True | 6.7.7 | Online | 1 | | A6D82670D8 | Leaf | node1 | 3309 | Running | True | 6.7.7 | Online | 1 | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ ``` Then run `sdb-admin remove-leaf` on each leaf in availability group 2: ```shell sdb-admin remove-leaf --memsql-id 4DAE7D1F54 -y ``` ```shell sdb-admin remove-leaf --memsql-id 52CA34CD0C -y ``` Run `sdb-admin list-nodes` again to verify only the two leaves in availability group 1 are listed. ```shell sdb-admin list-nodes -r leaf ``` ```output +------------+------+-------+------+---------------+--------------+---------+----------------+--------------------+ | MemSQL ID | Role | Host | Port | Process State | Connectable? | Version | Recovery State | Availability Group | +------------+------+-------+------+---------------+--------------+---------+----------------+--------------------+ | 74BBE83C45 | Leaf | node1 | 3308 | Running | True | 6.7.7 | Online | 1 | | A6D82670D8 | Leaf | node1 | 3309 | Running | True | 6.7.7 | Online | 1 | +------------+------+-------+------+---------------+--------------+---------+----------------+--------------------+ ``` ## Step 2. Update the *redundancy\_level* value On the master aggregator run: ```sql SET @@GLOBAL.redundancy_level = 1; ``` This updates the current configuration and sets the cluster to run in redundancy-1 operation mode. In addition, update the SingleStore configuration file on the master aggregator to make sure the change is not lost whenever it is restarted. ```shell sdb-admin list-nodes --role master -q | xargs -I % sdb-admin update-config --memsql-id % --key redundancy_level --value 1 --set-global -y ``` ## Step 3. Re-add leaves into availability group 1 (optional) Optionally, you can re-add the deleted leaves into the availability group 1. This also requires rebalancing partitions and clearing the orphan ones. List the nodes in your cluster so you know which ones to add back in: ```shell sdb-admin list-nodes ``` ```output +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | MemSQL ID | Role | Host | Port | Process State | Connectable? | Version | Recovery State | Availability Group | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | 43F1B836D3 | Master | node1 | 3306 | Running | True | 6.7.7 | Online | | | E4921A995C | Aggregator | node1 | 3307 | Running | True | 6.7.7 | Online | | | 74BBE83C45 | Leaf | node1 | 3308 | Running | True | 6.7.7 | Online | 1 | | A6D82670D8 | Leaf | node1 | 3309 | Running | True | 6.7.7 | Online | 1 | | 4DAE7D1F54 | Unknown | node1 | 3310 | Running | True | 6.7.7 | Recovering | | | 52CA34CD0C | Unknown | node1 | 3311 | Running | True | 6.7.7 | Recovering | | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ ``` To re-add the leaves into the availability group 1, run the following on the leaf nodes you previous removed: ```shell sdb-admin add-leaf --memsql-id 4DAE7D1F54 ``` ```shell sdb-admin add-leaf --memsql-id 52CA34CD0C ``` Run `sdb-admin list-nodes` one more time to show the leaves added back into the cluster, but in availability group 1. ```shell sdb-admin list-nodes ``` ```output +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | MemSQL ID | Role | Host | Port | Process State | Connectable? | Version | Recovery State | Availability Group | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ | 43F1B836D3 | Master | node1 | 3306 | Running | True | 6.7.7 | Online | | | E4921A995C | Aggregator | node1 | 3307 | Running | True | 6.7.7 | Online | | | 4DAE7D1F54 | Leaf | node1 | 3310 | Running | True | 6.7.7 | Recovering | 1 | | 52CA34CD0C | Leaf | node1 | 3311 | Running | True | 6.7.7 | Recovering | 1 | | 74BBE83C45 | Leaf | node1 | 3308 | Running | True | 6.7.7 | Online | 1 | | A6D82670D8 | Leaf | node1 | 3309 | Running | True | 6.7.7 | Online | 1 | +------------+------------+-------+------+---------------+--------------+---------+----------------+--------------------+ ``` Next, rebalance the cluster by running [REBALANCE ALL DATABASES](https://docs.singlestore.com/db/v9.1/reference/sql-reference/cluster-management-commands/rebalance-all-databases.md). ```sql REBALANCE ALL DATABASES; ``` The cluster will now contain orphan partitions - in fact, the old replica partitions. Orphan partitions can be shown by running `SHOW CLUSTER STATUS`, and deleted by running on the master aggregator: ```sql CLEAR ORPHAN DATABASES; ``` *** Modified at: April 29, 2024 Source: [/db/v9.1/user-and-cluster-administration/high-availability-and-disaster-recovery/managing-high-availability/disabling-high-availability/](https://docs.singlestore.com/db/v9.1/user-and-cluster-administration/high-availability-and-disaster-recovery/managing-high-availability/disabling-high-availability/) (An index of the documentation is available at /llms.txt)