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, ...
- 1,484
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 ...
- 6,169
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 ...
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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/...
- 4,478
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 ...
- 3,918
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)...
- 6,169
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 ...
- 1,720
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 ...
- 197k
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 ...
- 101k
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-...
- 197k
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.
- 197k
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:
...
- 6,169
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.
- 197k
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....
- 272
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....
- 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 ...
- 4,751
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 ...
- 244k
2
votes
Multipath in linux for 2 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 ...
- 8,851
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.
- 23.1k
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 ...
- 121
1
vote
Centos 7 - install and mount fc multipath disks
It's OK. The underlying devices are not being hidden in any way.
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 ...
- 4,478
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 ...
- 17.7k
1
vote
How to make RAID controller rescan devices
Restart the out-of-sync controller (eg c1)
/opt/MegaRAID/storcli/storcli64 /c1 restart
- 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=...
- 11
1
vote
Accepted
Does changing vmware datastore multipathing policy disrupt connectivity
Generally not no but it would be useful to know exactly what make and model your array is as not all support the active/active ALUA model that RR best serves.
- 101k
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 ...
- 131
1
vote
Seeing Multiple Partition for same LUN
When device is connected, kpartx creates DM devices for found partitions. I see fdisk found at least one partition, but it may be incorrect about remaining. As fdisk man page on RHEL7 says: fdisk does ...
- 1,100
1
vote
Accepted
Fiber multipath fails: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
Finally issue is resolved
Error: TECH PREVIEW: DIF/DIX support may not be fully supported.
I constantly saw this message in dmesg during the time of issue and Keep on ignoring this message
On ...
- 713
1
vote
SAN, ISCSI and Multipath (MLAG?)
This is a case where you should follow your storage vendor's guidelines.
I don't know who will be consuming your SAN resources, but the general approach should be:
Your regular servers using LACP ...
- 197k
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