Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [multipath]

The tag has no usage guidance.

0
votes
0answers
19 views

I can't unrepresented LUN (SAN) devices from server [duplicate]

I've 22Tb LUN from SAN Storage (HITACHI) on my Linux Server(CentOS 6.7). I configure multipath for this LUN, and now I want to remove it. The storage team detaches the LUN from my server and when I ...
1
vote
1answer
35 views

Formatting/creating file system on multipath volume for ZFS on Linux?

I inherited a ZFS on Linux (CentOS) storage pool and I have a faulty multipath device (mpathah) in my pool: raidz3-6 DEGRADED 0 0 0 ... ... mpathba ONLINE ...
0
votes
0answers
31 views

Can't restore PV metadata

I have a corruption problem on a PV (within a multipath, don't know if it matters). The base system is a CentOS 7 and the volumes are hooked up via iSCSI to an external storage. I found the LVM UUID ...
0
votes
0answers
17 views

Auto start and stop iscsi session

In SLES12 with systemd service running, I need iscsi session to stop and start automatically. The steps I need to follow is as follows. On stopping. a)Umount partitions b)Logout iscsi session On ...
0
votes
1answer
43 views

Multipathing on VMware ESXi is missing

I'm trying to configure a storage multipathing on VMware web client. I'm running the version 6.5.0, build 6765664. The problem is that on my storage section I can't find the option about multipathing. ...
0
votes
0answers
18 views

creating LV in clustered LVM gives 'Error locking on node' after pvresize

We have two CentOS 6.7 hosts that both use cLVM to access LVs on the same iSCSI-LUN (no LV is accessed by both hosts at the same time). The exact stack is [iSCSI-LUN] - [multipath] - [cLVM] - [vg ...
1
vote
1answer
29 views

RedHat: MultipathPackage Compatibility

I have an old RedHat5 server I can't upgrade the OS and new san XtremeI/O storage EMC recommended to install device-mapper-multipath 0.4.9-72 as a native multipath package.But the only available ...
0
votes
0answers
492 views

Centos 7 - install and mount fc multipath disks

I tried to install multipathing on a Centos 7.5 host following some links like https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/dm_multipath/mpio_components https://www....
1
vote
0answers
194 views

How to rescan missing multipathd paths?

I have multipath configured in ubuntu 14 server but strangely the number of path available for each device is different where the 5TB disk have 4 path and 4TB have 3 path. I have reloaded the ...
1
vote
1answer
120 views

Why multipath devnode change after reboot?

As I command multipath -ll, the output show like this. ocr3 (149455400000000000000000001000000ca0200000d000000) dm-9 IET,VIRTUAL-DISK [size=980M][features=0][hwhandler=0] \_ round-robin 0 [prio=0][...
1
vote
1answer
47 views

How to modify the “dm-*” value?

As I command multipath -ll, the output show like this. ocr3 (149455400000000000000000001000000ca0200000d000000) dm-9 IET,VIRTUAL-DISK [size=980M][features=0][hwhandler=0] \_ round-robin 0 [prio=0][...
1
vote
3answers
720 views

resizing partition using multipathd

redhat 6.3 with a multipath xfs partition. i have already increased the LUN and need to reflect the increase in the filesystem. using xfs_growfs will not work yet unless i increased the partition ...
0
votes
1answer
118 views

How to fine-tune iscsi-multipath queueing timeout?

I'm tuning the configuration for a multipath iscsi on a Centos 6 server. At the moment I'm using the following parameters for path retry: ... polling_interval 1 no_path_retry 12 ... That means, 'if ...
5
votes
1answer
1k views

How to make RAID controller rescan devices

I have the following setup: A single server with two LSI MegaRAID SAS 9380-8e controllers which are both connected to two 60-bay disk shelves while roughly following the design by Edmund White (see ...
1
vote
0answers
30 views

Notification on iscsi/multipath failure

I'm running iscsi-initiator combined with multipathd on a CentOS machine. How can I effectively be notified (e.g. via email) when one of the paths goes down? I can't find any suitable option on ...
0
votes
0answers
188 views

redundant routes not added to kernel routing table

I am running some tests on multiple Centos7 boxes with quagga/zebra and ospf routing. Kernel is 3.10.0-514.el7.x86_64 In one testcase I ended up having multiple routes with same weight from node01 to ...
0
votes
1answer
235 views

How to disable disk device user-friendly names in a RHEL 7 kickstart file

We're right now in the process of deploying a set of fibre-channel connected hosts with multipathed root disks. The installation is automated through foreman, so we boot vie PXE and run anaconda with ...
3
votes
2answers
178 views

Does changing vmware datastore multipathing policy disrupt connectivity

We have several VMware ESXi hosts accessing multiple datastore stored on a fiber channel SAN. We have found that some of the hosts are still set to "Most recently used" mode for their multipathing ...
0
votes
0answers
194 views

Correct filtering of raw devices which are multipath components out of LVM

I have a HP MSA P2000 FC with dual controllers, dual HP SAN switches and a couple of servers with QLogic "ISP2532-based" 8G dual-port cards. Everything is connected "each to each" way. The OS is ...
0
votes
1answer
149 views

How does packet reordering occur in MPTCP, and how does it affect performance?

I am trying to understand how MPTCP differentiates itself from "normal" TCP implementations running over multiple paths. Specifically, I want to know whether the best impementations of TCP are really ...
1
vote
2answers
227 views

In Infiniband can I use the same port for IPoIB traffic as well as RDMA traffic?

Good day, and my disclaimer that I am no IB expert and have not worked on IB directly yet. My question seems a trivial one, yet I could not find anything in google that answers it. Question: In ...
3
votes
1answer
209 views

multipath on iscsi target is it posible?

Is it possible to configure multipath on target iscsi SAN? I configured multipath on vmware iscsi initiator and it's work but bouth flows goes on the one SAN storage port with the IP but is it posible ...
0
votes
1answer
135 views

Linux Multipath

We have 3 hosts which are under oracle RAC cluster, recently we have seen lot of multipath path missing on all the 3 hosts and sometimes these hosts reboot automatically. current scenario is on host ...
0
votes
1answer
67 views

Seeing Multiple Partition for same LUN

Anyone knows why I am seeing multiple device for the same LUN?I checked with storage team they only exposed 360000970000196801239533036304532 for this server but why I am seeing these many partition(...
5
votes
2answers
293 views

only one of two SFP ports reachable on iSCSI SAN

I have a server with HP NC523 dual 10GbE network card and HP MSA1040 storage with dual 10GbE iSCSI-controller. Both ports on NC523 are configured as a bond. The ports on MSA have different IP-...
6
votes
4answers
3k views

Fiber multipath fails: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK

I am trying to copy(~7TB of data using rsync) between two server in same data center in the backend its using EMC VMAX3 After copying ~30-40GB of data multipath start failing Dec 15 01:57:53 test....
6
votes
2answers
600 views

SAN, ISCSI and Multipath (MLAG?)

I'm a bit confused regarding the setup of a SAN with ISCSI and multipath. We are upgrading our network to 10Gbit, so there are 2 10Gbit switches that are configured with MLAG for normal ethernet ...
5
votes
1answer
254 views

Refresh uuid of physical device

I'm trying to clone a LUN on a server and present it to the same server and am running into UUID oddities. I don't create partitions on the LUN, just create a PV and then LVM on top of that so I can ...
-1
votes
1answer
75 views

Race condition in active/active clusters

DM-Multipath document says that multipathd support active/active clusters with some policies such as round-robin. However, there is some racing problem in this kind of clusters. For example, assume ...
0
votes
0answers
163 views

How to do Multi WAN routing based on latency/distance to the target IP

I have two different internet connections available (DSL & LTE), and I'm building a router to "combine" those. What I would like to achieve: The routing should happen based on the latency or ...
0
votes
1answer
75 views

Fujtisu Eternus DX80 change iSCSI Discovery Reply Mode

I have a configuration mistake in my dx80 and the system is already in production. I have to set "iSCSI Discovery Reply Mode" at "Host Response" configuration to "All - Reply All Ports (Default)". Is ...
1
vote
2answers
384 views

ESXI 6.0 u2 multipathing configuration with group by prio

Is it possible to change the path grouping policy of ESXI 6.0 multipathing to group_by_priority? In essence I want to work with the grouping priorities given by a SAN storage. I didnt see any specific ...
2
votes
1answer
1k views

open-iscsi initiator on linux does not see the passive side of an active/passive open-e target

I have a Linux server running SLES11 SP4 which uses open-iscsi and multipathing to connect to a LUN that is presented from an Open-E DSS v7 storage cluster with active/passive failover. The Linux ...
0
votes
0answers
40 views

No w/s in iostat output even though wMB/s is high

I am trying to format a 2 TB SAN based block device (/dev/mapper/mpathb). Even though, mke2fs has been running since over one hour without completing, iostat -z -x -m 10 output in a separate terminal ...
2
votes
1answer
1k views

How do I set up the default route on a Linux router with dual ISP links?

So, here's the situation. I have dual ISP links currently active and working for routing traffic from my network, with a very similar iptables setup to the accepted answer at Load balancing & NAT-...
1
vote
2answers
3k views

Mounting multipath devices by UUID in fstab

I have several multipath iSCSI LUN's formatted as ocfs2 filesystems. They are part of an Ubuntu 14.04 cluster using local heartbeat. This all appears to be working fine if I mount them manually after ...
4
votes
2answers
989 views

multipath, device mapper, and disk i/o scheduler

We have two machines with a multi path SAS controller, each with 12 physical disks attached. We were looking into some I/O speed oddness, and noticed that on one machine, where /dev/mpath/mpath*p1 ...
0
votes
1answer
2k views

multipathd not working after restarting

Multipathd is not working, OS: CentOS 6.5 x86_64 [root@localhost ~]# rpm -qa|grep multipath device-mapper-multipath-libs-0.4.9-87.el6.x86_64 device-mapper-multipath-0.4.9-87.el6.x86_64 I m getting ...
1
vote
1answer
44 views

Multipath Drive Association

So i have an issue were the drive mappings for the servers will not line up even though the configs for them match exactly.. The main problem is the path for the drives keeps switching. foo# ...
0
votes
0answers
147 views

Backup strategy for LVM file sytem on NFS file server connected to SAN

I have setup a server (CentOS) on which I have connected to several LUNs from a SAN via iSCSI then multipath, resulting in multiple physical volumes I can use for LVM (dm1 ...). From the file server, ...
1
vote
0answers
500 views

Linux multipath 1 lun not using all paths other luns OK

A new 50gb lun was added to the rhel5.8 linux server and we did a scan to detect and add. However multipath -ll shows that the 50gb lun is using only 1 path while the old existing luns are on 2 paths....
1
vote
1answer
9k views

Create file system on multipath volume

I'm completely new to linux admin and file system. Recently we acquired an HP MSA P2000 san. I've setup the disk into a vdisk and created 3 volumes on it. On Centos 7, I've also setup the multipath ...
1
vote
0answers
238 views

Windows Server 2012R2 Backup

We have deployed Windows Server 2012R2, which by using the Windows Server Backup was backup on the drives connected from SAN. SAN disks connected through multiple paths using Windows Multipath-IO. ...
5
votes
3answers
2k views

Can't attach iSCSI with multipathing in Citrix XenServer

Dear people of the world. I have a problem reattaching an iSCSI target on XenServer after a reboot. Whenever I try, I get several errors. Here's me in the attach screen on the redundant storage ...
1
vote
1answer
5k views

lvextend: New size (3071999 extents) matches existing size (3071999 extents)

I configured LVM on a 12TB device with 1 partition. I then tried to extend the LVM across a second 12TB device with 1 partition. vgextend worked, but lvextend doesn't see the space on the second ...
0
votes
1answer
673 views

Multipath configuration is ignoring drives after /dev/sdaa, /dev/sdab, etc

I have a bare metal server running on Softlayer. It has many Consistent Performance iSCSI storage devices attached in a multipath configuration. One of the devices, represented by /dev/sdaa1 and /dev/...
3
votes
0answers
2k views

XenServer 6.5 iSCSI MPIO with point-to-point links (without a Switch)

I'm doing some experiment with iSCSI MPIO between FreeNAS 9.3 and two XenServer 6.5 hosts. I would like to use iSCSI MPIO to serve as VM storage. Pretty common environment, but without a switch to ...
1
vote
0answers
361 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 ...
3
votes
2answers
812 views

FC-Multipath: Which path_selector performs best?

So I learned that since Red Hat 6 it is possible to choose between 3 algorithms for loadbalancing between different paths to my FC-SAN, the default dumb round-robin - and new - queue-length and ...
0
votes
0answers
2k views

VMware ESXi RDM Shared Disk and Multipathing

I have set up a RAW mapped storage device which is shared between 3 VMs. In the guest OSs the disk shows up fine but when I try to set up multipathing I can only see one path. In the virtual machine ...