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26
votes
7answers
7k views

SQL Server disk design on an ISCSI SAN

Its standard practice to separate log and data files to separate disks away from the OS (tempdb, backups and swap file also) Does this logic still make sense when your drives are all SAN based and ...
7
votes
4answers
14k views

What is the difference between LVM and LUN

Both seem to be a virtualization layer on top of physical disks. I'm having a hard-time understanding each of them and the difference between them.
6
votes
5answers
844 views

LUNs and virtual machines

I have HP P2000 + XenServer solution working. What I'm thinking about is how to create LUNs for 20 virtual machines. Separate LUN for every VM ? It gives me ability to backup the specific virtual ...
4
votes
1answer
2k views

Considerations for spanned volumes with SAN's LUN.

I want to know, before going forward, what I can expected in lost of performance (or not) of creating Windows spanned volumes from LUN delivered by a SAN ? I don't know which kind of SAN is (we don't ...
3
votes
3answers
3k views

What are your recommendations/best-practices for vDisk/datastore/LUN management with VMWare ESX

Obviously there's an infinite variety of ways of carving up your raw SAN LUNs to provide VM boot and data vDisks - but what methods do you use, what are their pros/cons, and are there any good ...
3
votes
2answers
440 views

LUN and VMFS 5 sizing assistance

I am working on setting up our vSphere 5 environment. With vSphere 5 you can go > the 2TB VMFS datastore size that you were capped at with in 4.x, etc. What size datastores are people using and ...
2
votes
4answers
503 views

Drobo Thin Provisioning: What happens when you run out of space?

I'm thinking about getting a Drobo S to add some storage on a Windows Server 2008 R2 box. The Drobo offers thin provisioning. While I will only have 4.5TB of space initially, I'd like to use thin ...
2
votes
3answers
604 views

Exchange 2010 VMDK disk design

I am deploying Exchange 2010 on a single server on my VMware/SAN. We have about 100 mailboxes. I will be using normal VMDK disks, so my question is about the disk design. Should I put everything on ...
2
votes
1answer
311 views

What is the difference between LUN and array ? Arent they same?

Please clarify what do we mean by LUN and Array ? and if they are similar in meaning?. The confusion is because both are presented to specific servers by the combination of different Hard disks or ...
2
votes
1answer
435 views

SAN: is it better to have separate LUNs for operating system and data of virtual machines? [closed]

We have an iSCSI SAN that will be used as backing store for virtual machines. We use Xen and will directly present the LUNs as block devices of VMs (so there is no file system with files on it for ...
2
votes
1answer
2k views

Cannot extend existing data disk over 2TB on windows 2008 with dynamic and gpt part

As my D: disk is almost full (2TB) I extended the FC lun to 2.5TB. The new 500Go are seen by windows as "Unalloacted" as expected. I tried to extend the volume but windows says There is not enough ...
2
votes
2answers
2k views

iSCSI: LUNs per target?

My question relates specifically to ZFS/COMSTAR but I assume is generally applicable to any iSCSI system: Should one prefer to create a target for every LUN that you want to expose? Or is it good ...
2
votes
1answer
693 views

What is better to have more LUNs or more Storages

what is better to have - more LUNs or more Storages. Actually i have 1 storage ESXi per 1 LUN so there are about 15 LUNs and 15 storages. Now there is a kind of problem because the LUNs have different ...
2
votes
1answer
161 views

High availability using Fibre Channel and iSCSI in vSphere

I'm having a hard time understanding shared storage for high availability in vSphere. I have the following kit: 1 x Mac mini (ESXi 5.5 - part of vSphere) 1 x White box PC (ESXi 5.5 - part of vSphere ...
2
votes
2answers
1k views

How do you remove attached FC LUNS from CentOS 6?

We have a Qlogic QLE2560 HBA running on a Centos 6 server. I am needing to remove the attached LUNS remotely. I do not have any software from qlogic installed on the device. Their are 2 LUNS ...
2
votes
1answer
6k views

Is it possible to query the LUN ID of a list of windows server?

I'm trying a combination of FCINFO and PSEXEC to get the LUN ID (LUN NUMBER) used by servers, but i cant get this information directly from fcinfo. I've also try using WMI until i learned that i ...
1
vote
3answers
580 views

Do I have to have LUN on a iSCSI Target?

I am using Linux, and was wondering, if I could put LVM directly on a iSCSI target without a LUN?
1
vote
1answer
3k views

ESXi 4.1: how to make use of an iSCSI LUN bigger than 2 TB?

I have a ESXi servers (4.1 U1) connected to an iSCSI NAS, where 4 LUNS have been defined and presented to this host; all the LUNs are 3 TB in size. ESXi correctly sees the LUNs and acknowledges their ...
1
vote
2answers
832 views

Migrating the SAN lun in Linux

How to perform LUN migration in Linux (using LVM and native multipath) from one storage device to another storage device
1
vote
2answers
74 views

No LUN available to extend datastore

I have a HP DL380G5 with ESXi 5.5 and x4 146GB Sata disks in a RAID5 array. I have added one more disk to the server exactly as the other ones and, using SmartStart CD I managed to add the disk to the ...
1
vote
2answers
62 views

Multiple iSCSI LUNs to one Server

I'm reasonably sure i'm ok to do this, but I would love some confirmation. Simple question, can I have two LUNs from the same SAN attached to the same server? More detail: I have a HP MSA2000 SAN, ...
1
vote
1answer
2k views

ESXi 5 Add an existing lun to datastore without formatting

We have two hosts running VMWare ESXi 5.1.0. Both are connected to a RAID 5 array via iSCSI. The lun is an existing lun with vm on it but it is not reconized by the hosts after the reboot. it is ...
1
vote
1answer
557 views

Can I move a LUN from one phsical server to VM client?

I have a 500GB LUN created over our QNAP, and it's connected/binded to one server 2K3. It is identified on that server as disk E (Dynamic) I want to remove it from Server A, and connect it to a ...
1
vote
1answer
98 views

Why am I losing share access to my LUNS?

Question Rephrased: On our NAS, I have 3 LUNS created (I do not know if this is the cause of the problem). On my DC, I have attached them using iScsi, and have created them as a disk. On that Disk I ...
1
vote
2answers
1k views

Presenting Apple XServe RAID LUNs to XSan

I am working on a Final Cut Server setup with an associate and one of the things we need to do is setup XSan2 with two Apple XServe RAID units. I am able to get into the RAID Administrator and ...
1
vote
2answers
217 views

Adding storage to ESXi host

We have two hosts running VMWare ESXi 4.1. Both are connected to a RAID 5 array via iSCSI. We added three more disks to the RAID array. Now I need to assign the new storage somehow to the ESXi hosts. ...
1
vote
1answer
207 views

Can I re-assign the scsi letter for virtual floppy?

Having issues with oracle starting up in our cluster environment due to disks not lining up properly. For example, on the problematic host, I see the following. [1:0:0:0] cd/dvd AMI Virtual ...
1
vote
2answers
12k views

The Linux SCSI layer does not automatically remap LUN assignments

I've got some iSCSI/FC storage, currently using only iSCSI. I have in general no problems with mounting LUNs - under Linux and under Windows. Unfortunately - when I add LUN for my Linux iSCSI ...
1
vote
1answer
646 views

In Debian (>= 5.0 lenny) how to set scsi_mod's max_luns option?

The scsi_mod has this option max_luns which is the "last scsi LUN". How can I view the current setting and change it?
1
vote
4answers
801 views

Virtual system drive is split between separate LUNs

My hardware VMWare guy told me that a Win2008R2 server I have has a D drive that is split between two separate LUNs. He could not tell me if that's a good thing or bad just that it's not standard ...
1
vote
1answer
315 views

iSCSI LUNs on different VLANs

Is there any way to share different iSCSI LUNs on one iSCSI server on specific VLANs? IE lun1 would only be accessible via devices on eth0.3 and lun2 by devices on eth0.4. I'm using iSCSI Enterprise ...
1
vote
1answer
4k views

Assign and remove multiple LUNs from VMs on ESXi 4

We currently have a test environment where we create hundreds of LUNs on our SAN-attached storage array, export them to one or more (physical) servers, run tests on the data contained on the LUNs, ...
1
vote
2answers
671 views

Share SCSI DAS enclosure (vtrak m210p) between multiple servers?

I've got a Promise vTrak m210p subsystem. It supports LUN mapping & masking, and has two SCSI channels (2 VHDCI ins & 2 outs on rear of device). I believe this question will probably apply ...
1
vote
0answers
47 views

Does a dead LUN path cause an increase in I/O times on the remaining LUN path(s)?

We use an EMC SAN appliance. There are 2 'paths' from the cluster to the SAN. Today we experienced that one of the LUN paths was 'dead' (as reported in the windows event logs). Presumably the ...
1
vote
0answers
87 views

NPIV Fibre Channel how to make vHBA scsi_hostX persistent after reboot and libvirt

I'm using QLogic 8GB Fibre Channel HBA which has NPIV with CentOS6.5 I created the LUN on the SAN and did the zoning for the virtual WWPN. In CentOS I do the following to create a virtual HBA: echo ...
1
vote
1answer
315 views

Clariion CX300: Removing system disks from a RAID group?

I have a raid group that includes every disk my DPE2. I want to remove the system disks (0-4) from this RAID group. From what I read I should i put them in their own RAID group and avoid storing ...
1
vote
0answers
177 views

Presented LUN displaying 3 disks after fdisk -l

All, I appreciate in advance any useful responses to the following: One (1) 800GB LUN from external SAN was presented to 4 RHL servers (2.6.9-78.0.8 x86_64) Initial < fdisk -l > before reboot ...
1
vote
2answers
215 views

LUN device file names mixed

The following listings are from a Linux RHEL box. I'm a bit confused over the following inconsistencies. Here we have aliases defined for each LUN in multipath bindings file: mpath0 ...
1
vote
0answers
305 views

LUNs disappear after rebooting the ESX/ESXi host

A single LUN among from a group disappeared following the ESXI host restart. Neither the host nor the Vcenter can see it. I have four virtual machines on the LUN hiden now showing just unknown from ...
1
vote
1answer
426 views

Solaris: Clone/Recreate iSCSI target not backed by a ZFS Volume

Is it possible to re-create or clone an existing iSCSI target not backed by a ZFS volume? I ask because upon rebooting a X4500 Thumper, I was affected by this bug: ...
0
votes
2answers
1k views

What is the filesystem used to mount a LUN disk?

How do you mount a fresh LUN disk to your / ? Do you use ext3 or NFS for this ?
0
votes
3answers
220 views

How to share a fibre channel filesystem between 2 hosts?

I have 2 hosts in isolated networks (no network access from one to another). There is a storage system accessible over fibre channel from both hosts. Is it possible to have both hosts have a safe ...
0
votes
1answer
300 views

LUN storage disk in 2 servers, can't see the files

I have one LUN disk connected over FC with linux server ( with centos) and esxi server with VM in Centos. (Two machines work in different LAN's.) In both machines i see this disk. In VM i created the ...
0
votes
2answers
732 views

Expanding iSCSI LUNs (NTFS)

I have a 4TB iSCSI LUN that formated as NTFS in Windows 2008. I've shared this formated volume as a folder over SMB. When the capacity of this volume is not enough, I have to add more iSCSI LUNs, but ...
0
votes
2answers
201 views

Sharing a SAN LUN across 2 clients

I have an ISCSI SAN that we purchased to store images for our cluster (2TB of images). After reading, we probably should have gone with a NAS rather than a SAN, but back to the point. I'm going to ...
0
votes
1answer
149 views

How to rebuild my NAS

Today I have a QNAP TS-859U+ with 8 X 2TB disks in it. As it's was setup on day-1 it uses a single volume on a raid 5. The volume has currently a mixture of: 2 shared folders 5 iScsi Targets - ...
0
votes
1answer
243 views

Read LUN from dell SAN with a PC on linux

We are currently using a md3000i DELL SAN server with a RAID1. I would like to access the information on one disk from a workstation. The hard disk contains 2 LUN but I can only access the first ...
0
votes
3answers
15k views

Attach local disk to a VM in VMware ESXi

I'm sorry if this has been asked before. We are planning to attach a local SAS disk to a VM, so the VM can access the disk directly. We're using VMware ESXi 4. I have heard that this can be done ...
0
votes
1answer
111 views

Do I require a clustered file system to share a LUN via VMWare?

I want to avoid this: How can I use NTFS and iSCSI and not corrupt my SAN? On possbility I may have is to share out a LUN from my SAN and have other machines access that shared drive. In other ...
0
votes
2answers
2k views

File Server - One large LUN or multiple smaller LUNs?

We're about to replace a bunch of kit (servers, SAN etc.) and migrate our servers across from their current platform. Our file server has around 8tb of data on it right now, spread across 5 LUNs (all ...