SYSEXTERNLOGINS system table

CREATE TABLE SYS.SYSEXTERNLOGINS (
	user_id		 UNSIGNED INT NOT NULL,
	srvid		INT 	NOT NULL,
	remote_login		 VARCHAR(128),
	remote_password		 VARBINARY(128),
	PRIMARY KEY ( user_id, srvid ),
FOREIGN KEY REFERENCES SYS.SYSUSERPERM,
FOREIGN KEY REFERENCES SYS.SYSSERVERS
)

Each row describes an external login for remote data access.

user_id The user ID on the local database.

srvid The remote server, as listed in SYSSERVERS.

remote_login The login name for this user, for the remote server.

remote_password The password for this user, for the remote server.