Die iSCSI über 1 GBIT Ethernet Performance kann in dieser Liga mitspielen.
Maßnahmen wie Etherchannel und Portaggregation sind preiswert und leicht zu implementieren.
Desweiteren wird Ethernet im Endkundensegment technisch beherrscht, das komplizierte FC bereitet hier fast ausschließlich große Probleme.
Die Verbreitung von 4 GBIT FC ist dazu in der Regel nur sehr minimal (Marktrelevanz erst ab Mitte 2006).
Dennoch hat iSCSI FC Systeme in der Vergangenheit eher ergänzt.
Fibre Channel (FC) war bisher der unangefochtene SAN-Storage Sieger; es gab auch keine Alternativen.
Durch preiswerte 10 GBIT Ethernet Technik verändert sich die Situation aber radikal. Die Portkosten für 10 GBIT Ethernet betragen lediglich Bruchteile der FC/Port Kosten. Die Technik setzt sich in steigendem Maße und Umfang durch und findet rasante Verbreitung.
10 GBIT Ethernet über Kupfer ist auf CAT 7 bis 100 Meter sicher spezifiziert und absolut betriebssicher.
GBIT Ethernet SAN's sind dabei, die FC Ära zu beenden.
Die TCO Vorteile und das größere Storage/Applikationsserver Verhältnis sprechen für sich.
Hersteller von Storage Systemen haben ihre Hardware auf die benötigten größeren Prozessorressourcen angepasst.
Übersicht:
iSCSI is based upon existing industry standards, practises and applications that are known and understood by end users.
iSCSI is a network storage protocol that encompasses block level SCSI data in a TCP/IP frame, thus allowing servers to access storage resources over an existing IP infrastructure.
iSCSI is a combination of SCSI and Ethernet technologies that have been around for more than 20 years and are fully tried and tested.
iSCSI is a cost effective way to build SAN’s at much lower cost point, giving users greater consolidation in their environment.
The iSCSI storage protocol is supported by 99% of the major storage vendors and endorsed by Microsoft, IBM and Cisco therefore it is an industry standard.
iSCSI is an OPEN architecture that enables an optimised and cost effective TCO to be achieved and your TCO is protected for the future.
Fibre Channel is a TIED architecture that can only see an increase in TCO in the future.
iSCSI Advantages
Utilise your existing network
Traditional servers can be replaced by smaller cheaper low cost servers.
Adding more storage, no longer needs the servers to be taken down for upgrades.
Servers run more efficiently as they have less to manage internally.
Use non-proprietary storage SATA, SAS, SCSI, FC etc.
When replacing servers the data no longer needs to be backed up and restored. Just snapshot the data and re-mount the storage to the new server.
Reduced maintenance costs
Utilises all your disk storage and takes the guess work out of how much is required
Reduced management costs, as additional disk space can be easily added to the servers
About iSCSI:
iSCSI is a networking - data storage protocol that combines SCSI data blocks with Ethernet IP packets. SCSI commands are encoded in to Ethernet packets and then sent over Ethernet networks. When they reach their destination these packets are separated out using the off-load engine into Ethernet and SCSI commands and the data is then sent to the relevant device.
As iSCSI uses existing Ethernet switches, cables, routers the deployment costs are much lower than if you were to design a Fibre Channel SAN. Operating systems see iSCSI-connected devices as SCSI devices and are unaware that the SCSI device connected to the network resides across the room or across town.
iSCSI SAN
An iSCSI SAN will cost considerably less the reasons for this are:
Many manufacturers will be supplying Gigabit Ethernet cards with built-in iSCSI offload engines as standard.
No new investment in network architectures as an existing Gigabit network will suffice.
No new software as the device on an iSCSI network look like SCSI devices
iSCSI is fully supported by Microsoft, Cisco etc.
http://www.peripheralstorage.com/iscsi/images/iscsisan.pdf
Create a pool of centralised storage using iSCSI and install on each of the servers the iSCSI initiators, then use disk manager that are able to mount storage from pool to servers which can be Windows, Linux, UNIX, MAC or Novell based. These operating systems must support iSCSI and have an iSCSI initiator.
The centralised storage server can be Mirrored/RAIDED or Snapshot. If you put iSCSI TOE controllers in each of your servers, you can then boot from the centralised storage.
The major advantages are:
No dedicated specialised networks as in Fibre Channel Buy servers with no RAID controllers or Disk
As the storage is IP based you can serve up information across Wide Area Links or the Internet
Should a server fail, then the storage can be mounted on another server instantly
Reduces cost by buying smaller more compact servers
Backups are reduced because you can make snapshots and back them up during the day
One person can administer and control all you storage requirements from a single system and allocate disk on demand
Cut down on Backup Software Licensing costs as all you need to do is Snapshot or Mirror the information to another server and backup just one server!
This really is amazing technology and is supported by Microsoft, Cisco, IBM etc....
We guarantee you will save money in terms of storage management costs, server pricing and maintenance.
IP SAN
Storage area networks (SANs) are a tried and tested way to lower the total cost of ownership and increase the performance and availability of corporate storage resources. Because of this, SANs based on Fibre Channel technology have become the standard in many corporate data centers.
By enabling storage consolidation and an easy to use GUI, iSCSI Appliance IP SAN solutions enable organisations to provide pooled disk and network their enterprise data assets, improving enterprise data accessibility and availability and providing greater application uptime and flexibility than direct attached storage. iSCSI Appliance solutions are founded on a single, heterogeneous platform using industry-standard protocols IP and SCSI. Deploying an iSCSI Appliance IP SAN solution enables organisations to leverage existing investments to bolster infrastructure interoperability. Additional functionality can also provide local and remote Snapshots as well as clustered iSCSI Appliances for continuous data availability and uptime.
The world of today revolves around high speed, continuous access and availability of information and data.
An IP SAN has all the benefits of a Fibre Channel SAN without the cost and training implications.
