7 votes
Accepted

"Bad message" with a new SAN using multipath and iSCSI

That is normal behavior for a non-clustered file system. To use iSCSI SAN with Ubuntu compute servers, a clustered file system should be used. You should probably learn more about GPFS, GFS2, Lustre, ...
A.Newgate's user avatar
  • 1,483
6 votes
Accepted

only one of two SFP ports reachable on iSCSI SAN

Never use LACP or any other kind of network aggregation for iSCSI networks unless it was required by your SAN vendor. Use MPIO (Multipathing) instead.  Generally speaking, teaming creates a network ...
Net Runner's user avatar
  • 6,199
6 votes

Should I bond iSCSI network connections?

You can LACP NICs you're planning to use with iSCSI, but only in one case - if both "sides" (target & initiator) support so-called "multiple connections per session". If they don't or this feature ...
BaronSamedi1958's user avatar
5 votes
Accepted

Linux multipath: How to configure a single multibus path group

Have you actually measured the performance and found it degraded? You may actually find it's improved, although the difference may not be very large. The Dell PowerVault MD3860i seems to be an active/...
telcoM's user avatar
  • 4,588
4 votes

SAN, ISCSI and Multipath (MLAG?)

Since you have iSCSI SAN, I suggest you go with MPIO splitting iSCSI networks and utilize different subnets. LACP does same failover as MPIO, however comes with performance penalty due to unsupported ...
Mr. Raspberry's user avatar
4 votes

multipath on iscsi target is it posible?

I am not sure about your multi-path on exactly this SAN box model. So, I will elaborate a bit on multi-path in general. The idea of multi-path (for convenience I'll call it MPIO in the following text)...
Net Runner's user avatar
  • 6,199
4 votes

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

This looks to me like one of your SFPs has soft-failed... Look in your storage switch for errors on the port while you are doing a large copy. I had a similar issue recently where everything looked ...
Dre's user avatar
  • 1,835
4 votes

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

This is an HP ProLiant DL380 Gen9 server. Pretty standard enterprise-class server. Can you give me information on the server's firmware revision? Is EMC PowerPath actually installed? If so, check ...
ewwhite's user avatar
  • 198k
4 votes

"Bad message" with a new SAN using multipath and iSCSI

ext is not a cluster-aware filesystem, so the moment a second node mounts it it will be corrupted. This is because there's no common block locking mechanism, which there is with a cluster-aware ...
Chopper3's user avatar
  • 102k
3 votes

only one of two SFP ports reachable on iSCSI SAN

You're not supposed to use LACP "bonding" with iSCSI. This is a situation where you should be using MPIO multipath. Regardless, you won't be able to achieve 20Gbps speeds with this setup (one server-...
ewwhite's user avatar
  • 198k
3 votes

"Bad message" with a new SAN using multipath and iSCSI

Um... A SAN is not NFS. Unless you're using a shared/cluster filesystem, you can't just mount something ext4 onto multiple hosts.
ewwhite's user avatar
  • 198k
3 votes

How a failover in Active/Passive SAN multipath should be properly handled on Linux multipath system?

The back-end FC ports of each ISCSI module (also called as "MPX bridge" as it performs the role of ISCSI multiplexer from ISCSI to FC) on the EVA connects as a FC Direct Connect to HSV front-...
storsan's user avatar
  • 57
2 votes

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

I know that if you will change in /etc/sysconfig/mkinitrd/multipath MULTIPATH=NO on MULTIPATH=YES and at file /etc/multipath.conf - comment next: blacklist {devnode "*"} Turn on auto-load: ...
Net Runner's user avatar
  • 6,199
2 votes
Accepted

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

Absolutely, you can have IPoIB and RDMA on the same InfiniBand port. Regarding prioritization, InfiniBand can support multiple traffic classes. You can find information in this document: http://www....
haggai_e's user avatar
  • 272
2 votes

iSCSI multipath: should I keep all portals configured, even unreachable ones?

I have a similar setup using direct attached Proxmox hosts. The daemon.log was filled with 700K entries per day although the startup of the unneeded nodes was set to manual (which was sufficient at ...
Larsen's user avatar
  • 345
2 votes
Accepted

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

Most likely your new virtual disk had a VFAT filesystem on it and was not erased before you reused it. It's safe to use it with zpool replace -f but this will destroy any old data on the disk, as ZFS ...
Michael Hampton's user avatar
2 votes

Multipathing on VMware ESXi is missing

Configuration of multipathing can be done via the thick desktop client (even for 6.5) or via CLI or SSH in the server. cmdlets for the SSH - https://kb.vmware.com/s/article/1017760 https://kb.vmware....
P.Pauls's user avatar
  • 266
2 votes
Accepted

RedHat: MultipathPackage Compatibility

Have you tried getting the storage to work with the version of device-mapper-multipath natively shipped with Red Hat 5? It might work and besides Red Hat 5 is EOL so it's unlikely any vendor is going ...
bodgit's user avatar
  • 4,771
2 votes

Does changing vmware datastore multipathing policy disrupt connectivity

No, there's usually no impact. This setting can be changed on the fly, assuming the correct "plumbing" is in place.
ewwhite's user avatar
  • 198k
3 votes

Multipath in linux for 2 HPE 3PAR replicated storage devices

This requires a bit of technology outside the world of standard FC. Different vendors have different solutions. I know Hitachi, EMC, and Netapp all offer this, but it’s elaborate and involves, at ...
Basil's user avatar
  • 8,881
2 votes

ZFS and SAN: issue with data scrubbing

You're looking at the wrong spot. If you SAN faults under load, then you can't rely on it, period. Fix the SAN.
longneck's user avatar
  • 23.2k
2 votes
Accepted

ZFS and SAN: issue with data scrubbing

We were able to fix the setup. We set the proper option cachefile=none in order to avoid importing the zpool at startup with an unstable multipath configuration. We noticed that it happened that some ...
Benoit's user avatar
  • 121
2 votes

Non-valid paths in "multipath -ll" output

I found the issue. The previous attempts of multipath flush was not done cleanly. Once it was flushed, associated device references needed to be cleaned under /sys/class/scsi_device/. Set the device ...
Hem's user avatar
  • 121
1 vote

centos multipath /dev/mapper dont map partitions

skip_kpartx yes is the solution. defaults { user_friendly_names no skip_kpartx yes find_multipaths yes } from the man page of multipart.conf skip_kpartx If set to yes , kpartx will ...
Kordi's user avatar
  • 141
1 vote
Accepted

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

I have found a sufficient answer in this MPTCP paper. Essentially, MPTCP has a sequence order for the "overall" flow as well as for each flows. This means that MPTCP should, in theory, have no ...
Tama Yoshi's user avatar
1 vote

Centos 7 - install and mount fc multipath disks

It's OK. The underlying devices are not being hidden in any way.
Michał Sacharewicz's user avatar
1 vote

Why multipath devnode change after reboot?

To allow for hot-plugging and dynamic reconfiguration, you should not assume that the /dev/sd* device nodes will stay the same from one boot to the next. On a workstation with just a single AHCI SATA ...
telcoM's user avatar
  • 4,588
1 vote

How to fine-tune iscsi-multipath queueing timeout?

no_path_retry is not a timeout in seconds, but is the number of retries until the failure is reported to the upper block device (e.g. file system). It accepts queue as value, which means that retry ...
Mircea Vutcovici's user avatar
1 vote

How to make RAID controller rescan devices

Restart the out-of-sync controller (eg c1) /opt/MegaRAID/storcli/storcli64 /c1 restart
jeffre's user avatar
  • 11
1 vote

How to make RAID controller rescan devices

seems like the jbod option in the controller is disabled, try this command storclif64 /c0 show jbod and if the JBOD is OFF you can enable it using storclif64 /c0 set jbod=ON (storcli /c0 set jbod=...
Anand RL's user avatar

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