Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Surprisingly the performance was better than I expected. I haven't done any specific performance testing but its better than 10mb sec. We have a public network card for Exchange and SQL and a dedicated connection for HB and DRBD. On that some connection we connect the ISCSI to the main nodes of the cluster. It works well. It will never replace a true ISCSI server but it comes close enough for the price. > -----Original Message----- > From: drbd-user-bounces at lists.linbit.com [mailto:drbd-user- > bounces at lists.linbit.com] On Behalf Of Luciano Miguel Ferreira Rocha > Sent: Wednesday, April 05, 2006 1:16 PM > To: drbd-user at linbit.com > Subject: Re: [DRBD-user] Sensible maximum number of drbd devices > > On Wed, Apr 05, 2006 at 12:32:56PM -0700, Gary W. Smith wrote: > > One of the client sites that we setup we configured a matched set of > > VMWare servers. They had a need for a clustered Exchange server and a > > clustered SQL server. They also had a limited budget for what they > > wanted. Here is what we did. > > > > We setup VMWare on the two servers and created 3 virtual servers each. > > Node one was the linux-HA running DRBD and iscsi-target. Node two was > > Exchange and node three was the SQL server. Duplicated this on second > > environment. > > > > It works like a champ. Cost ~$5k for the two name brand servers, dual > > Xeons, 4gb ram and 250gb raid drives... > > > > So yes, it can be done on the same box and it can work great. I would > > recommend that you have the iscsi server running on the node that's not > > running everything else (otherwise disk performance becomes your issue). > > Are you sure about this? I'd expect the require round-trip on the > network to cause a more significant performance decrease or delay > increase: > > Exchange VM1 --- iSCSI, network ---> DRBD VM2 > | > +--> Disk write > | > DRBD VM1 --- DRBD protocol, network, data ---+ > | > + Disk write > | > + --- DRBD protocol, network, ACK ---+ > | > Exchange VM1 --- iSCSI, network, ACK ---+ > > While if the iSCSI server runs on the same physical, > Exchange->DRBD/iSCSI would be faster (virtual network interface), and > the block data would only be sent once over the real network interface. > > > -- > lfr > 0/0 > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user