By default, SQL Anywhere uses the names and passwords of its clients whenever it connects to a remote server on behalf of
those clients. CREATE EXTERNLOGIN assigns an alternate login name and password to be used when communicating with a remote
The REMOTE LOGIN clause is required only when the remote server requires a user ID and password for the connection. Having
an external login without a remote login allows the DBA to control who can access the remote server and tells the remote access
layer that logging in to the remote server does not require a user ID and password. For example, the directory access server
class requires an external login for restricting access to the directory server, but remote login is not needed because the
directory server does not perform user ID and password validation.
The password is stored internally in encrypted form. The remote-server must be known to the local server by an entry in the ISYSSERVER table.
Sites with automatic password expiration should plan for periodic updates of passwords for external logins.
CREATE EXTERNLOGIN cannot be used from within a transaction.