Chapter 8 - Configuring Frame Relay/PPP And T3
Upgrading Software 
For some customers, access to remote sites in accomplished solely by a T3 
connection.  Usually a software upgrade will stop the system being upgraded, perform 
the upgrade and then restart it.  If T3 port was upgraded in this way, the upgrade 
would fail as the T3 link was taken down.  Instead, T3 software upgrades modify only 
the software on the disk. You must schedule a reboot in order to run the new version 
of T3 software.
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