You do not have the PROCESS privilege at /usr/bin/pt-online-schema-change line 4456, <STDIN> line 1

Question

I'm experiment with the pt-online-schema-change tool with a MySQL 5.7 database hosted by AWS RDS. I have gotten past a few different configuration issues and when I run a dry-run everything looks good but I get this error immediately when I try and run the command with the execute flag.

I'm running this on Amazon Linux 2 which is RHEL 8 based (I believed). I'm not sure if this is related to my Linux permissions or my database permissions. I'm running this as root on my workstation and my MySQL user has fairly elevated permissions.

I found a Percona forum post on this but it's from a long time ago with only one response and the response doesn't provide any concrete advice on how to resolve and I'm not sure the response is valid based on other internet researches about linux process permissions.

Any advice on how to resolve this error? Do I need to add more permissions for my MYSQL user or something on the linux command line side?

$ pt-online-schema-change D=my_db,t=my_table,h=my_host.com,u=my_user --alter="drop COLUMN ios_notification_token" --alter-foreign-keys-method="auto" --ask-pass --preserve-triggers --execute
Enter MySQL password: 
You do not have the PROCESS privilege at /usr/bin/pt-online-schema-change line 4456, <STDIN> line 1.

Answer 1

I ended up needing to grant additional privileges to the MySQL user being used for the migration by pt-online-schema-change.

Assuming the DB name is my_db and the user is my_user, running these commands should give the tool the permissions it needs to perform the migration.

GRANT PROCESS, SELECT, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO my_user;
GRANT ALL PRIVILEGES ON `my_db`.* TO my_user;