Use smsconnectsc to connect to the other System Controller when it is inacessible by its IP address

sms-svc@sc:~ $ smsconnectsc
Attempting to determine remote SC power state. This may take some time.
Attempting to get TTY connection state. This may take some time.
TTY connection is OFF.
About to connect to other SC. Do you want to continue (yes/no)? yes
Attempting to set TTY connection state. This may take some time.
connected

• Solaris