Data; Delta Snaps; Dhcp; Domain - American Megatrends StorTrends 1100-P User Manual

But, there could be situations that the remote snap group at time T(x-n) may NOT be
available – could have been deleted by an automatic schedule. In this scenario, the
system will do one of the following operations:
•
First it will try to find matching most recent snap group across ACTIVE and
PASSIVE. If available, then the PASSIVE will be rolled back to the matching snap
group and replication will start from there.
•
If no matching snap groups present that is safe (out of disaster), then there is no way
the replication can continue with given parameters. In such scenarios, the PASSIVE
volume data will be wiped out and replication will start from the beginning.
DAS
Direct Attached Storage. As the name implies, this is basically any storage device that is
directly attached to the server. DAS can be a JBOD (Just-a-Bunch Of Disks) unit, hard
disk drives internal to the server, external USB hard disk drives, and so on. Suitable for
small installations. Limitations includes, inefficient provisioning, storage manage through
the server, adding capacity usually means adding another server (resulting in duplicated
overhead information), and scaling requires downtime.

Data

Distinct pieces of information usually formatted in a special way.

Delta Snaps

In Snap Assisted Replication, always only the difference between the old and new
snapshot is replicated to the secondary – essentially these are the new data written during
the new snapshots life-cycle. These delta data between the snapshots will be written
directly to the volume on the secondary and once all delta data for a particular snapshot
are replicated, a snapshot will be taken. The snapshots in the secondary are essential to
provide recovery points. In the event of a failover, the active volume in the secondary
cannot be used as it may have some snapshot data that is not fully consistent. On a
failover to secondary system, the ITX will automatically rollback to the latest available
snapshot in the secondary. This provides a consistent image to start with upon a failover
in the secondary system.

DHCP

Dynamic Host Configuration Protocol. Enables individual computers on an IP network to
extract their configurations from a DHCP server.

Domain

A group of computers and devices on a network that are administered as a unit with
common rules and procedures All devices sharing a common part of the IP address are
said to be in the same domain.

Domain Controller

A server with a Microsoft® Windows® 2000/NT operating system and Active
Directory™ enabled.

Domain Name

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