Questions tagged [storage-area-network]
A SAN is a Storage Area Network, for providing block-level access to storage subsystems across a network.
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What is the difference between SAN, NAS and DAS?
What is the difference between SAN, NAS and DAS?
sevugarajan
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Pay no attention to that SAN behind the curtain
Once upon a time, I built my own SQL servers, and had control over drive configuration, RAID levels, etc. The traditional advice of separation of data, logs, tempdb, backups, (depending on budget!) ...
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What is a Storage Area Network, and which benefits does it have over different storage solutions?
I'm proposing this to be a canonical question about enterprise-level Storage Area Networks.
What is a Storage Area Network (SAN), and how does it work?
How is it different from a Network Attached ...
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Tuning iSCSI storage
This is a Canonical Question about iSCSI we can use as a reference.
iSCSI is a protocol that puts SCSI commands as payload into TCP network packets. As such, it is subject to a different set of ...
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Testing whether jumbo frames are actually working
Is there a command to test whether jumbo frames are actually working? i.e. some sort of "ping" that reports whether or not the packet was broken up along the way.
I've an ESXi host with an Ubuntu VM ...
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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 ...
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How should I set up my Fibre Channel (FC) network?
How do FC switches work, and how should I configure mine?
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What kind of storage do people actually use for VMware ESX servers?
VMware and many network evangelists try to tell you that sophisticated (=expensive) fiber SANs are the "only" storage option for VMware ESX and ESXi servers. Well, yes, of course. Using a SAN is fast, ...
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Cheapest iSCSI SAN for Windows 2008/SQL Server clustering?
Are there any production-quality iSCSI SANs suitable for use with Windows Server 2008/SQL Server for failover clustering?
So far, I've only seen Dell's MD3000i, and HP's MSA 2000 (2012i), which both ...
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Why would a heavily disk intensive application run faster on a SAN than on a Physical Disk?
Why would a heavily disk intensive application run faster on a SAN than on a Physical Disk? I would have expected the Physical disk to be slightly faster but in fact the process ran 100 times faster ...
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150 TB and growing, but how to grow?
My group currently has two largish storage servers, both NAS running debian linux. The first is an all-in-one 24-disk (SATA) server that is several years old. We have two hardware RAIDS set up on it ...
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Best practice for assigning private IP ranges?
Is it common practice to use certain private IP address ranges for certain purposes?
I'm starting to look into setting up virtualization systems and storage servers. Each system has two NICs, one ...
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ZFS and SAN -- best practices?
Most discussions of ZFS suggest that the hardware RAID be turned off and that ZFS should directly talk to the disks and manage the RAID on the host (instead of the RAID controller).
This makes sense ...
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Best Practices for virtualizing servers onto the SAN?
Alright, so I want to start leveraging my SAN a little more than I have been, and at the same time, take advantage of ESXi.
Currently, I've got an array of Dell PowerEdge 1955 blades connected to a ...
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How many disks is too many in this RAID 5 configuration?
HP 2012i SAN,
7 disks in RAID 5 with 1 hot spare,
took several days to expand the volume from 5 to 7 300GB SAS drives.
Looking for suggestions about when and how I would determine that having 2 ...
Tom
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Are there no downsides to NetApp SAN solutions other than price? [closed]
We have pretty much decided on a NetApp solution for our first SAN. Given that, I've been tasked with finding as much reason not to go with NetApp as I can. We like to do this A) so we know what we're ...
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SAS vs. Nearline/MDL SAS - What is the difference?
As subject I guess, looking at SAN's and most vendors offer 10k or 15k "proper" SAS drives, many also offer 7.2k MDL/Nearline SAS drives.
Does anyone have an authoritative explanation of the ...
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Choosing a SAN technology for 100s of VM Web Servers
The Problem
We have an issue with performance on an existing platform, so I'm turning to the hive mind for a second opinion on this. The performance issue so far relates to IOPS rather than ...
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Is my new Oracle DBA talking sense
When we setup FC LUNs for our MSSQL boxes we rarely have to present them with more than about 8 distinct LUNs of various kinds (Quorum, MSDTC, TempDB, Data, Logs, Backup and a few others).
We have a ...
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SQL Server Files Local or NAS or SAN?
I have to install a new Server with SQL Server 2008, What do you recommend, One server with Raid 10 or the Files in a NAS?
What about iSCSI should I use it?
What about SAN?
The server has 4Gb of ...
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How to get free space from mounted drive Redhat 7
In our VM infrastructure, we have clustered hosts going to a SAN.
What i am trying to figure out is how much "white space" is left over when deleting files within our Redhat servers. On our Windows ...
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Linux goes to swap while plenty of RAM installed
I have a linux box that is used as SAN storage. It is equipped with 14 SATA HDDs and the only software it run is iscsi target and zabbix agent. This is physical box, not VM.
The RAM size installed is ...
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SSH / SCP Server on Windows [duplicate]
Possible Duplicate:
What is a good SSH server to use on Windows?
Can anyone on the SF community recommend a trustworthy/easy to set up SCP server for windows. I do not want to go through the ...
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What's the point of SAN routing?
I'm familiar with extending fabrics by adding more switches to it, but i don't get why sometimes it's better to do routing between fabrics (considering all the switches are from the same vendor, using ...
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Disk Speed Performance in a SAN
We are currently looking into buying a SAN, and have some concerns over the speed of disks we are going to put into the array. We would normally have gone for 15k disks over 10k every time, but one of ...
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IQN Naming convention
I've seen a lot of information about how IQN's should be formatted, but there's not a lot of information on how to build them. I'm kind of a newb when it comes to iSCSI, and i have it working, but I'm ...
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How do you backup a SAN?
long time reader, first time asker :)
I have been reading up a lot on iSCSI and SANs in general and I believe I have been able to answer most of my questions and concerns on the topic, but this one ...
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Cost effective and frugal SAN solution for under $5000?
I will have 3-4 servers that will need SAN access for both IOPS performance, and raw storage capacity. The limit is, cost. Solutions I have seen run $10,000+ for anything 9TB or higher.
If I were to ...
Jason
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iSCSI, multiple initiators for the same LUN
I have a web application that is distributed over 3 servers. These 3 servers need a shared storage to access files. Since iSCSI is just a protocol, not a filesystem, it will not have any ...
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Can you connect a SAN directly to a HBA with Fibre Channel?
I am in the process of sourcing our company's first SAN as we have the need for high availability/shared storage. I have noticed fibre channel switches are extremely expensive, and for redundancy we ...
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Using non-certified hard drives in Dell MD3220 storage array
Is it possible to use non-certified hard drives in a Dell MD3220 storage array? I ended up getting 3 new drives that were the EXACT same model number as the existing ones. Then I bought the drive ...
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Is there a Distributed SAN/Storage System out there? [closed]
Like many other places, we ask our users not to save files to their local machines. Instead, we encourage that they be put on a file server so that others (with appropriate permissions) can use them ...
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VMware VMFS5 and LUN sizing - multiple smaller datastores, or 1 big datastore?
With VMFS5 no longer having the 2TB limit for a VMFS volume, I'm considering which scenario would be more beneficial overall:-
Less LUNs of larger size, or
More LUNs of smaller size.
In my case, I ...
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Correct placement of devices on a Fibre Channel fabric
We're getting a pair of new 8Gb switches for our fibre channel fabric. This is a Good Thing since we're running out of ports in our primary datacenter, and it'll allow us to have at least one 8Gb ISL ...
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Is brand-name NAS overpriced?
NetGear's ReadyNAS 2100 has 4 disk slots and costs $2000 with no disks. That seems a bit too expensive for just 4 disk slots.
Dell has good network storage solutions too. PowerVault NX3000 has 6 disk ...
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SAN with a few SSD drives, or lots of old fashioned HDDs?
My company is trying to figure out what type of SAN to purchase. This is specifically for database servers that are becoming IO constrained (storage is DAS right now, but we're hitting the limit of a ...
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Why MPIO instead of 802.3ad Team for iSCSI
Doing my first server to iSCSI target and I thought i would be off to a running start by teaming my NIC on the server (conventional 802.3ad team).
However, from many online sources I see this is NOT ...
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ZFS stripe on top of hardware RAID 6. What could possibly go wrong?
I have 36*4TB HDD SAN Rack. RAID controller did not support RAID60 and not more than 16 HDDs in one RAID group. So I decided to make 2 RAID6 groups of 16HDD or 4 of 8 HDDs.
I want to get all storage ...
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Mixing HBAs in a failover cluster?
I have a two server failover cluster, and for various reasons - they're on mismatched hardware.
One has Emulex HBAs installed, the other Qlogic.
I'd be twitchy about using two different makes/...
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Fibre Channel LUN rescan and QLogic
I have a serious problem with a SAN storage array connected to a Linux box through Fibre Channel. Here is the configuration :
Debian with plain vanilla linux 2.6.27.25
Fibre controller QLogic 4Gb ...
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Cheap but Highly Available Shared Storage? [closed]
my group is in the market for plentiful storage. We traditionally used big-iron FC-attached SANs, but they are way expensive and provide much more performance than we require.
We want highly ...
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Why should iscsi traffic be isolated?
Why should iscsi SAN traffic be isolated? I'm trying to explain to my network guy why we should isolate the traffic.
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I want a file search like 'Everything' for network shares [closed]
If you haven't heard of Everything, I can't recommend it enough. It will index all of your files in seconds and search through them in the blink of an eye.
Everything only works on local NTFS ...
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Setup of HP ProCurve 2810-24G for iSCSI?
I have a pair of ProCurve 2810-24G that I will use with a Dell Equallogic SAN and Vmware ESXi.
Since ESXi does MPIO, I am a little uncertain on the configuration for links between the switches. Is a ...
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What is "deduplication"?
I mean, I can look up the dictionary definition, but why is everyone suddenly talking about it in reference to virtual tape libraries? What's "new" here so that it's so much in the news lately?
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"Mandatory" free space on a SAN?
I'm not an expert of SANs, I'm writing here to get some clues on continuous and exasperating problems we're having which our supplier seems not to be able to solve.
we own an ENHANCE ES3160P4 SAN ...
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Can i pause VM's while power-cycling iscsi storage array
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 ...
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Can I dynamically expose an entire SCSI host over Fibre Channel, preferably in Linux
Is it possible to expose an entire SCSI host dynamically (an LSI HBA or RAID card) over Fibre Channel, if so how?
Preferably on Linux (perhaps targetcli) and with disk hotplugging support. (i.e. ...
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Array free space requirement
The general rule of thumb is don't use more than 80-85% of your capacity, otherwise performance degrades sharply, and other bad stuff may happen.
On a 8TB array, this comes out to around 1.6TB of ...
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Windows share: The specified network name is no longer available
We've got an EMC NX4 SAN box serving a CIFS share to a number of Windows Server 2008 R2 app servers. The app servers are using the CIFS share to serve lots of image files (~2500 ops/sec on the share), ...
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