I was looking at Dell Equalogic devices, the PS4100E. It says you can have two PS4100 boxes for 36TB each. Am I reading that right? What if I want to have more space? Can I span to more 4100E devices or do I have to have another set of boxes, another set of IP address? Is there anything I can do to make it so I have a switch and one IP address for an [...]

We are considering adding a SAN. I have two choices right now, the Dell MD3000 and the Dell MD3000i, 15 x 146Gb san drives. Naturally the latest model is more expensive (2x as much), but can someone tell me if the speed difference is considerable to be worth the extra cost? Our DB on Sql Server 2008 r2 is only about 30Gb and not expected to grow much over the next few years. We have [...]

I have installed the scsi-target-utils package on CentOS and I used it to perform a discovery. The discovery did give me an active session. I restarted the iscsi service but I do not see any new devices (fdisk -l). I see in /var/log/messages that my connection is operational now. I’m not sure how to debug this further. Can someone direct me into fixing this? discovery: iscsiadm -m discovery -t sendtargets -p 192.168.0.155 returns: 192.168.0.155:3260,-1 iqn.2009-02.com.twinstrata:cloudarray:sn-1d07c1b62d4ec8f3 [...]

So we just picked up a new PS6100x and I’m wondering if I need to setup the ethernet channels myself or is it automatic? It’s configured in an HA setup; dual controllers connected to redundant cisco switches with a 10GE interconnect. On the controller, I’ve enabled eth0-3, each with it’s own IP 172.16.0.50-53, and a group IP address of 172.16.0.10. Do I need to bond the interfaces on the switch or will the controller take [...]

I am about to implement a SAN here using a HP P2000; the SAN itself is on-order (ETA a couple of weeks) so in the meantime I’m getting the rest of the equipment up and running. The SAN has dual-controllers and I’m going to multipath the whole setup. Here is what the plan is for the SAN to look like: I’m got the switches installed and configured; they are dedicated switches with all ports in [...]

I have a server with ESXi 5 and iSCSI attached network storage(4x1Tb Raid-Z on freenas). Those two machines are connected to each other with Gigabit ethernet, and a procurve switch in between. After a while, if I have many(4-5 or more) vms running, they start to get un-responsive (long delays before anything happens). We are trying to find the reason behind this. Today we looked at esxtop, and found that DAVG of that iSCSI LUN [...]

I have just detected that in one of my hosts (this is a virtual machine run by a cloud provider) there is a process eating up some bandwidth: NetHogs version 0.6.0 PID USER PROGRAM DEV SENT RECEIVED 4617 root iscsid eth0 170.808 7.957 KB/sec 13300 root sshd: user1 [priv] eth0 0.000 0.841 KB/sec 26042 nagios ssh eth0 0.745 0.789 KB/sec TOTAL 171.656 10.287 KB/sec I have googled a bit about this iscsid process (new thing [...]

Windows is adding a route for a local address (10.0.0.90 – my fileserver) with a gateway of (10.0.0.138 – this is my gateway), the gateway only has a 100Mbs link so all of my fileserver bound traffic is being reduced to 100mbs, if I unplug the gateway it jumps back upto 1000mbs. The fileserver also functions as the DHCP (isc) server (i am booting from iSCSI with IET and iPXE). Also the machine with the [...]

Read performance on our SAN is slow under certain workloads. When we compare this to some local storage, we find the local storage performing 2x as fast. The SAN performs well with a high Queue Depth, and poorly with a low queue depth. However, the local storage performs well with a low Queue Depth. I’d like to know the reason for this occurring and find out what the specific limiting factor is in this situation. [...]

Unfortunately I may have to power-cycle my storage array. In the context of using KVM with libvirt managing the Virtual Machines where i need to power-cycle the storage array, is it possible or even advisable to : pause the VM’s flush and turn off multipath log out of iSCSI sessions update and power-cycle storage array. then follow the reverse course of re-establish iISCSI sessions restore multipathing resume VM’s Any advice is welcome. Asked by janos [...]