SingleStore DB

Dedicated Admin Connections

To log in to a dedicated admin connection, you should first log in to the machine where the master aggregator is running. If a master aggregator is not running, then log into a child aggregator.

Then execute:

singlestore -u root --socket '/<installationpath>/data/memsql.sock' -p

Note

You can use either the SingleStore command-line tool or the MySQL command line tool.

This uses a Unix domain socket to designate that this is a dedicated admin connection. This is only available in the file system and cannot be used over a network, which is why you must log on to the aggregator before connecting using this method.

Once you log in, if commands do not run, you can kill connections and queries to free resources to allow others to connect to the system.

A similar approach will also allow you to log on to a leaf node directly, if necessary. The connection is node-local.

Here is an example of how to setup a dedicated admin connection:

sh-4.4# cd /var/lib/memsql
sh-4.4# ls
5871bce2-e2fa-4934-ad92-5fb842c74fef  a36fb148-c8e2-4132-a7cd-c7694e43336d  nodes.hcl  nodes.hcl.lock
sh-4.4# cd a36fb148-c8e2-4132-a7cd-c7694e43336d/
sh-4.4# ls
auditlogs  data  memsql.cnf  plancache	tracelogs
sh-4.4# cd data
sh-4.4# ls
blobs		     ingest_staging  memsql_id		memsqld.pid	  roots      staging_bottomless
datetime_to_version  logs	     memsql_proxy.sock	memsqld_safe.pid  snapshots  tempblobs
ephemeral_errors     memsql.sock     memsql_role	persisted_errors  spill      temprestoreblobs
sh-4.4# ls -tla memsql_proxy.sock
srwxrwxrwx 1 memsql memsql 0 Nov  4 22:03 memsql_proxy.sock
sh-4.4# pwd                           
/var/lib/memsql/a36fb148-c8e2-4132-a7cd-c7694e43336d/data
sh-4.4# singlestore -u root --socket '/var/lib/memsql/a36fb148-c8e2-4132-a7cd-c7694e43336d/data/memsql.sock' -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 58
Server version: 5.7.32 MemSQL source distribution (compatible; MySQL Enterprise & MySQL Commercial)

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singlestore>

The engine variable, max_dedicated_admin_connections, determines the number of dedicated admin connections allowed. Default is 5.