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2
votes
3answers
3k views

Linux / Multipath not using all paths, and won't use queue-length path_selector?

I have the following hardware: 2x SuperMicro servers (128GB RAM, 2x 8 core AMDs) 2x/server LSI SAS2008 PCIe MPT-Fusion2 HBAs (2 SAS ports per card) 1x LSI CTS2600 DAS with 24x W.D. 15.7k RPM 600GB ...
1
vote
1answer
180 views

Multipath only sees 2.0T of 4.8T [closed]

I use multipath on 64Bit Ubuntu. If I do multipath -ll it finds my devices, but reports them as 2.0TB instead of the 4.8T they should be. Any idea why this is the case? Example output: ...
2
votes
2answers
1k views

Multipathd load balancing on md3200i

I'm working on setting up a cluster of servers with an iSCSI MD3200i SAN for shared storage. Everything is working well but I have one small detail I can't seem to get working. Multipath seems to only ...
5
votes
1answer
599 views

Home-grown SAN — topology ideas?

I'm interested in hand-rolling a SAN solution on Linux with the following technologies: iscsi mdadm raid lvm multipath xfs/gfs/??? teamed NICs Hardware-wise, I'm thinking of 2 x gigE (or better) ...
6
votes
3answers
972 views

/dev/disk/by-id/scsi-* links pointing to sdX instead of multipath device

We have two similar SLES10SP2 servers both using multipath on the same devices from the same storage array. On one server, the /dev/disk/by-id/scsi-* devices properly point at the multipath devices: ...
6
votes
2answers
6k views

How to enable multipath I/O for NFS-backed VMware ESXi storage?

Right now I have 3 VMware ESXi hosts using 4Gb fibre channel to our NetApp for storage. I'd like to switch to NFS over 10Gb ethernet. Each ESXi server has two 10Gb ethernet ports and each controller ...
3
votes
2answers
3k views

Good NFS multipath solution

I have a couple of servers serving exactly the same content through NFS to several webfarms, all the servers involved are running CentOS 5 The content between both NFS servers is replicated using ...
0
votes
1answer
5k views

is multipath -F safe? (flush all unused paths)

from multipath manpage: -F flush all unused multipath device maps is this a safe operation? I have a bunch of old dead paths and would like to clear them out, but want to make sure it's ...
2
votes
1answer
2k views

RDAC MPP driver erratic path fail-over errors

In my central syslog I can see a some instances ofo the following error from LSI's RDAC multi-pathing driver for Linux. [RAIDarray.mpp]MY_NICE_STORAGE_ARRAY:1:0:7 Cmnd-failed try alt ctrl 0. vcmnd SN ...
0
votes
1answer
1k views

How to dismount SAN device - multipath on Ubuntu

I have to disconnect SAN connected thru FibreChannel to Ubuntu. How can i do this? root@fs2:/# umount /srv/media umount: /srv/media: device is busy. (In some cases useful info about processes ...
2
votes
3answers
2k views

lpfc + multipath + ubuntu - path keeps switching

I am having issues configuring multipath using Emulex (lpfc). Although I do not detect data corruption the SAN administrator has a tool that shows that the paths are being switched every 20 seconds or ...
0
votes
1answer
567 views

LVM issues when adding a newly-carved LUN from a Clariion - pvcreate fails

This seems to be a semi-common issue asked, but I have not yet found a good solution. I try the following: [root@localhost ~]# pvcreate /dev/sdc Can't open /dev/sdc exclusively. Mounted filesystem? ...
5
votes
3answers
998 views

Why is my MPIO connection to the SAN capped at 1 Gbps when using Linux?

I'm connecting a RHEL5 box to a Dell EqualLogic PS5000X and seeing a maximum of 1 Gbps even while using MPIO with three gigabit NICs. I have all three interfaces on the PS5000X and three dedicated ...
0
votes
1answer
401 views

Same hard disk reported twice in Red Hat (SAN and multipath)

I use two Q-Logic HBA's on one server which have access to the same LUN. Red Hat (and gparted also) sees the LUN as two seperate disks (sda, sdb). Is this normal? Thanks!
0
votes
1answer
842 views

Adding multipath to server and change lvm to use new devices

Hi I have a server running RHEL5 (HP Proliant DL365) connected to a EVA. LVM is used for the SAN disks like this /dev/sdav VolGroup09 lvm2 a- 150.00G 90.00G /dev/sdbi VolGroup08 ...
5
votes
5answers
380 views

What is the least expensive way to obtain 1,000s of public IP addresses?

What is the least expensive way to obtain 1,000s of public IP addresses? I'm needing to serve secure (https) pages for 1,000s of SSL certificates, and need a separate IP address for each SSL cert. ...
9
votes
1answer
2k views

Improving SAS multipath to JBOD performance on Linux

I'm trying to optimize a storage setup on some Sun hardware with Linux. Any thoughts would be greatly appreciated. We have the following hardware: Sun Blade X6270 2* LSISAS1068E SAS controllers 2* ...
1
vote
2answers
942 views

Debian and Multipath IO problem

Basically the situation is, I have a box running Debian, the box internally has an Intel SCSI RAID controller which is controlling 2 hard drives in RAID1 mode which is where the OS is installed. ...
1
vote
1answer
11k views

How do you “fix” a faulty path in device-mapper-multipath

I have a multipath config that was working but now shows a "faulty" path: [root@nas ~]# multipath -ll sdd: checker msg is "readsector0 checker reports path is down" mpath1 ...
10
votes
2answers
806 views

Adding 60TB Storage to an SLES 10 Server

I have to add some archive\staging storage to an SLES 10 Server. The requirement is to present fairly large volumes (9-20TB each approx, 60TB or so in total) that will be used to store archive data ...
4
votes
2answers
1k views

What is Multipath I/O?

What exactly does "Multipath I/O" mean?
3
votes
2answers
3k views

Solaris Multipathed I/O - Physically Removing a Disk

I am a Solaris newbie. I have a Solaris 10u8 machine that is running an attached J4400 and some internal drives. We're using multipathed SAS I/O (stmsboot; mpathadm), so the device mount points have ...
1
vote
5answers
11k views

EMC PowerPath or MultiPath?

We are using a SAN for our datastorage. I recently got the SAN connected to a CentOS 5.3 server by using the EMC PowerPath software along with the Navisphere Agent running on CentOS. However I have ...
2
votes
5answers
253 views

When is storage considered highly-available?

I've read in several places people describing the following configuration as Highly Available: 2 servers (sometimes with multiple HBAs) each connected via multiple SAS cables to one RAID enclosure ...
3
votes
3answers
1k views

Merit and demerits for various Linux fiberchannel multipath options

On our Linux servers, we currently use HPs qla2xxx drivers, because it has multipathing (active/passive) built in. The are, however, various other options, like Red Hats device-mapper-multipath with ...