KERNSAFE - iSCSI SAN Software and Storage Virtualization

iSCSI device is datastore used for other business applications such as virtualization and database, so iSCSI device is very important and must be backup.
In KernSafe iSCSI SAN, we can use physical device and virtual images as iSCSI target, so we can treat them as separated:

1. Physical Disks:
   
   • a) User can use hard disk mirror software to create software RAID1, this is built-in feature in Windows, user can easy to create mirror with other disks.
   • b) User can use KernSafe HAReplicator to create hard disk / volume mirror with other hard disk / volume, this software is working in the kernel level and transparent to user.
   • c) User can also use synchronous or asynchronous replication in iStorage Server, which is real-time but not working in kernel level, any data bypass to iSCSI transport layer (for example, if user do any modification directly to physical disk) won’t be backup, so be careful to use this method.
2. Virtual Images:
   Backup an iSCSI image files is very easy, just copy it to other place, but for now we only suggest real-time methods.
   
   • a) User can use Windows Shadow Copy (VSS), use VSS can create snapshot in any time on a volume which hold image files.
   •  b) User can use synchronous or asynchronous replication in iStorage Server to real-time backup to another server or another disk. As the image files normally can’t be directly used by other applications, so this method is safe and easy to use.
   • c) Create snapshot or automatic snapshot replication in iStorage Server, with this method, user can revert changes if data in iSCSI devices is something wrong.
   • d) User can use hardware RAID, once one hard disk is damaged, user won’t lose data, this is also a good backup method.