[postgis-users] VMWare and PostGIS

[Martin Spott]

"Stephen V. Mather" wrote:

> Ah, so a SAN may not be the best option either.  Well, we're
> narrowing the options down...  .

"SAN" is a synonym which applies to a lot of different techniques. Not
all of them are affected by the same penalties as iSCSI is ....  Some
people claim that the only reason why iSCSI survived was the limitation
to only this technique for shared/failover storage in VMware  ;-)

There are a few more options, depending on your budget, location and
topology.  If iSCSI is a must and target and initiator are in the same
location, then you might consider buying a few Infiniband HBA's.  iSCSI
over InfiniBand can be really nice, because it allows to circumvent all
the latency related to the IP stack (except from login/handshaking) by
doing the relevant I/O over remote-DMA (iSER).
If iSCSI is *not* a must and target and initiator are still in the same
location, FibreChannel might be a viable option.  It's not very
expensive but still almost as fast/low-latency as a local disk.  With
selected storage systems you can even do FC over raw Ethernet
infrastructure (FCoE) *without* IP.

Both, iSER as well as FC are "SAN", but substantially different from
traditional iSCSI.

Cheers,
	Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
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