SUSE supports two different upgrade and migration methods. For more information about the terminology, see Section 17.1, Terminology. The methods are:
All upgrades that are executed from the running system are considered to be online. Examples: Connected through SUSE Customer Center, Subscription Management Tool (SMT), SUSE Manager using Zypper or YaST.
When migrating between Service Packs of the same major release, we suggest following Section 20.4, Upgrading with the Online Migration Tool (YaST) or Section 20.5, Upgrading with Zypper.
Offline methods usually boot another operating system from which the
installed SLE version is upgraded. Examples are: DVD, flash disk,
ISO image, AutoYaST,
plain RPM or PXE boot.
Upgrading from SUSE Linux Enterprise 11 SP4 to SUSE Linux Enterprise 12 SP3 is only supported via an offline upgrade. See Section 19.0, Upgrading Offline
Upgrading from any SUSE Linux Enterprise 12 LTSS version or SUSE Linux Enterprise 12 SP1 or SP2 to SP3 is supported using all offline and online methods. See Section 19.0, Upgrading Offline and Section 20.0, Upgrading Online.