How to set tidb global system variables in filesystem

Question

Can global system variables (eg: https://docs.pingcap.com/tidb/stable/system-variables) be set on the filesystem (eg: tidb.toml) before startup or can they only be set via a client?

eg: set @@global.tidb_distsql_scan_concurrency = 10

Answer 1

Global variables are stored in TiKV. The system variables table is initialized when the first time bootstrap the TiDB. There is none way to set it before startup.