according to the release notes (https://www.suse.com/releasenotes/x86_64/SUSE-SLES/11-SP3/), ext4 is fully supported as a file system. But in order to gain r/w access, you’ll even have to separately activate the according feature during module load:
[h=3]14.4.2 ext4: Runtime Switch for Write Support[/h]
The SLE 11 SP3 kernel contains a fully supported ext4 file system module, which provides read-only access to the file system.
Read-write access to an ext4 file system can be acquired by setting the rw kernel module parameter to 1, either through module load time options or after module load through the kernel sysctl interface. Be aware that this action will render the kernel module and the kernel as the whole as unsupported upon first read-write mount of an ext4 file system.
ext4 is not supported for the installation of the SUSE Linux Enterprise operating system.
Since SUSE Linux Enterprise 11 SP2 we support offline migration from ext4 to the supported btrfs file system.[/QUOTE]
The Ext4 Howto at https://ext4.wiki.kernel.org/index.php/Ext4_Howto states that “It’s safe to use it in production environments, but as any piece of software, it has bugs (which are more likely to be hit in the first stable versions). Any known critical bug will be quickly fixed.”
Are you actually limited to SP2, or was that a “reference to earlier statements on the web”?