Questions tagged [multipath]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0
votes
0answers
10 views

How do common MPTCP schedulers behave by default?

Multipath TCP (MPTCP, RFC 6824) is a protocol that layers a "virtual" TCP connection over several "physical" TCP connections such that ordering and other TCP guarantees are preserved but seamless path ...
0
votes
0answers
19 views

How to mount external storage 3PAR after rebooring automatically?

My host connected to 3PAR via 2 FC port. I actually mount storage with multipath successful. But whenever server was reboot, path mounted the external storage not found. If I add mount command into /...
7
votes
2answers
154 views

Should I bond iSCSI network connections?

I'm setting up some iSCSI storage (Lenovo) along with a physical server running RHEL7. The server has 2 NICs for the main LAN (bonded) and 2 NICs for the iSCSI network. The Lenovo storage has 4 ports ...
1
vote
1answer
90 views

How do I specify a preferred source address for IPv6 multihome clients?

My ISP provides an IPv6 prefix delegation but with a dynamic prefix. I want a publicly routed static prefix for some local services, so I also have a Hurricane Electric tunnel set up, which means ...
-1
votes
1answer
39 views

DM multipath along with local disk

I have one /storage partition which is created from /dev/sdc local disk which is in LVM, now i want to extend it. we have 1 disk free which is a multipath disk over iscsi. can i add this disk in the ...
1
vote
0answers
62 views

Scsi Path is failing

I am very new to multipathing concept. I am trying to troubleshoot an issue with multipathing however, I am not sure if it's an issue with multipath configuration. Server is connected to storage over ...
2
votes
0answers
132 views

iSCSI Multipath to block device on zfs pool in ubuntu

I have succesfuly set up zfs pool, created block on it , and created iscsi target. The target is visible from esx host and i can us it as datastore. steps i did: zpool create tank raidz2 sdb sdc ...
1
vote
0answers
201 views

Multipath routing with linux kernel 4.19

I have the following two devices tun-1 and tun-2. They have the same ip address 21.2.0.3 and the same gateway 21.2.0.1 (each gateway points to a different device/VM, they just happen to have the same ...
3
votes
1answer
797 views

Linux multipath: How to configure a single multibus path group

I have just upgraded a functional Ubuntu 16.04 host to 18.04 and am now having issues with multipath. Package versions: * multipath-tools 0.7.4-2ubuntu3 * open-iscsi 2.0.874-5ubuntu2.7 I have a Dell ...
1
vote
1answer
45 views

centos multipath /dev/mapper dont map partitions

On SERVER1 I have the following output of dmsetup info -C: Name Maj Min Stat Open Targ Event UUID ...
1
vote
1answer
368 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
1answer
450 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. ...
1
vote
1answer
33 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
1answer
2k 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
761 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
547 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
129 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
2k 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
186 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
2answers
3k 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
46 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
1answer
336 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 ...
2
votes
2answers
298 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 ...
1
vote
0answers
343 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
298 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
447 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
319 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
224 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
94 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
387 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
5k 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
952 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
537 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
78 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
1answer
79 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
420 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
2k 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
45 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
2k 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
3answers
4k 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 ...
3
votes
2answers
1k 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
3k 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
48 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
202 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
639 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
11k 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
242 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
3k 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 ...
2
votes
1answer
7k 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
842 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/...