iSCSI Multipathing - interesting questions

Similar Questions

• iSCSI multipath vs network redundancy?

  If I have a redundant network, say a VMkernel port on a vSwitch with two VMnic, maybe Port ID load balancing and the two vmnic goes to two different physical switches and there are redundant links on all switches between the ESXi host and iSCSI SAN and it is Rapid Spanning Tree set up, and there is a kind of Etherchannel / Link aggregation on the iSCSI Server , but only a single IP address...

  Is there an advantage to configuring iSCSI multipath and let the VMkernel manage failover, rather than let the network itself, make sure that there is a path between the host and the target?

  Primary storage provider use several IP for storage NIC (in some cases two different networks).

  With the VMware multichannel modules, you are limited to only one path (at that moment) to a LUN, but the seller might have is multichannel modules, or of course, you can use LUN more have used more of paths.

  Bandwidth could be interesting with several virtual machines... or I/O loads.

  André

• iSCSI multipath on a distributed vSwitch?

  I read that there are problems with this and I'm pretty positive, I read that it is still not supported in one of the documents ESX4u1 (although for the life of me I can't find this text of presentation this morning).  Is this even a question?  And if so, can someone explain why exactly this is not working?

  I'm documenting a config proposed for deployment using cards dual 10GbE and I do research using iSCSI multipath and dvSwitches.  Which raises another question, on a channel 10GbE same multipathing necessary?

  
  
  -Justin

  If you are talking about the use of links in the port, then you must use conventional switches for this purpose.  It is in the notes version of vSphere

  vExpert

  VMware communities moderator

  -KjB

• Why several vmkernels for iSCSI multipath?

  I'm a little confused about the iSCSI Multipathing. What is the reason for the creation of two vmkernel interfaces and then use command line tools to link them to a new vmhba? Is it different for the use of a software iSCSI initator on a vSwitch with multiple VMNIC, connected to different physical switches?

  There is the same discussion in thread Russian vmug.

  iSCSI Multipathing is not on the trail, its about us pairs - initiators (interfaces vmk) and targets.

  If you have two targets

  • and you need to fail over only - 1 vmk is enough (NIC in Active mode / standby)
  • If you need loadbalacing
    • and you can use the aggregation of links + Hash IP - 1 vmk is sufficient (PSP is Roundrobin and NICs in active/active mode)
    • If you cannot use THE - vmk 2 are needed.

• iSCSI multipath with Distributed Virtual Switch error

  Ive followed the iSCSI SAN guide and have iSCSI multipathing works well with a regular virtual switch. Ive cancelled all configurations and have begun to see if I can get this working with a dVSwitch.

  I get the error "Add Nic failed in IMA"

  Someone at - it ideas?

  I recently worked on a case of iSCSI with VMware support and they mentioned a known issue with iSCSI and dVS, this is also described in the release notes, but may still have a problem. You can contact the technical support for confirmation.

  • ESX/ESXi 4.0 4.0 does not support the compatible ports with DVS binding configuration VMkernel network interface cards

  If you configure compatible with vNetwork Distributed Switch port binding NICs VMkernel, the operation fails if you enter esxcli swiscsi nic adds - n vmkx d vmhbaxx and vmkiscsi-tool - V - a vmkx vmhbaxx orders through the service console or the vSphere CLI.

  Workaround: Use only inherited vSwitch VMkernel NIC for port binding.

  =========================================================================

  William Lam

  VMware vExpert 2009

  Scripts for VMware ESX/ESXi and resources at: http://engineering.ucsb.edu/~duonglt/vmware/

  repository scripts vGhetto

  VMware Code Central - Scripts/code samples for developers and administrators

  http://Twitter.com/lamw

  If you find this information useful, please give points to "correct" or "useful".

• How can I vote for an interesting question on the dedicated forum?

  Hello

  I know that Muse is a brand new application, but there are several relevant question - in my opinion - that should be considered first.

  After much navigation (!), I found a forum where you can vote for these interesting questions users have faced.

  Unfortunately, I'm unable to vote for one of theses messages if I am connected.

  Is there something to do to get this "right to vote"?

  I really want to participate in this improvement, just gimme the tools to do!

  Thanks for your response

  We know a few emails as of late in the ideas of the forums section and thus our Admin had turned off their.

  I have re-enabled them so you can vote and add ideas and apologize for the inconvenience.

  -j

• iSCSI Multipathing

  This feature is in part?

  Hi John

  When you say iSCSI multipathing are you askingif initiator iSCSI s/w supports iSCSI CIDs? As other posters have said, even in iSCSI 3.5.x load balancing / redundancy is supported. One of the best plates of search (over and top the iSCSI SAN configuration guide) is "TA2213 - VMware Infrastructure 3 storage: iSCSI implementation and best practices" presented at VMworld 2008.This apron covers some details very good implementation around load balancing and path multiple configurations.

  In vSphere, we made a lot of improvements iSCSI.  For example, we have ways to set up the iSCSI initiator ESX to each port allows to establish a session to a target.  This means more paths for failover or load balancing. It is documented in the new SAN iSCSI for vSphere config guide which will be online soon.

  hope this helps

  Lee Dilworth

• iSCSI Multipathing - each path does refer to a specific target IP address?

  Dear Experts,

  I just set up a 6.0 ESXi host and a Synology NAS ds2015xs MPIO Multipathing. On the side of ESXi, I created two dedicated VMkernel with a physical NIC adapters each and every other network cards set to unused. I then added the adapters to the software iSCSI adapter in ESXi. On the side of SIN, I configured both interfaces in the same subnet as the VMkernel adapters. I then created a target which allows multiple iSCSI sessions, add LUNS and allowed access to the target for the IQN of the ESXi iSCSI Software adapter name.

  Back on the side of ESXi, I added a static discovery entry manually adding addresses to IP of NAS devices and target IQN. After a new analysis of the storage, ESXi showed two paths to the interface of the SIN for which I entered the IP address as a static discovery entry:

  

  With this configuration, multiple paths does not--once to stop the interface on the NAS, ESXi don't miss not automatically during the second interface of the NAS. After you have added a second static discovery entry with specifying the same target, but the second IP address of the NAS, ESXi showed all four lanes - two at each interface on the NAS:

  

  With this configuration, Multipathing works as expected. If an interface on the NAS fails, ESXi will automatically use a path for the second interface.

  In fact, it makes sense. At first, I was wondering about whether it is correct that I have to manually enter each interface of the target in order to obtain the corresponding paths to it. I first thought that I just need to enter an IP address of the target and that MPIO uses a kind of magic to automatically discover the paths to other interfaces available on the NAS. Later, I saw that this is the case when using dynamic discovery instead of static discovery. However, the same dynamic discovery adds all interfaces of the SIN as entries in static discovery. Once I have delete one of these entries in the list, the corresponding paths are also deleted.

  So my correct understanding that always information path refers to the corresponding IP address of the target and that a way will stop working once the corresponding IP address is no longer available?

  Thank you

  Michael

  When you configure access to storage, it is always important to follow the recommendations of the supplier. Not only to learn how the program setup the IP configuration, but also for the way political (e.g. Fixed, MRU, Round-Robin).

  Regarding your question, many storage arrays are configured with the extra VIP (virtual IP address) or IP address of the group, which is then used to configure the target (or another) dynamic on the ESXi hosts. When an initiator connects to such a VIP or group IP, the target will respond with all of its associated IP addresses. If this isn't an option for your storage device, you must provide all the IPS target manually (as you did).

  André

• Reduce the number of iSCSI Multipathing in paths

  I'm experimenting with performance iSCSI on NAS. Currently I have 4 NICs on the host and 4 NICs on the NAS. That leaves me with 16 channels for iSCSI data store. I would like to disable multipathing so I find myself with 4 paths. I would try having NIC1 on the host go on the NAS NIC1 and NIC2 on the host then goes to NIC2 on the NAS, so on and so forth. Is this possible? I saw that I could disable paths but I did anyway to say which way goes to which nic so that I might finish with 4 paths all on the same network adapter. Any help would be appreciated.

  I found that if I broke to the top of each of the 4 NIC I used for iSCSI in different subnets traffic and then set the 4 network cards on the NAS in the same subnets I could get the number of paths down to 4. However with adapter for iSCSI for the VMware software there is no way to have more than 1 NIC of the flow value. Round Robin will use only 1 NETWORK with a value of debit card while I was stuck with the help of only 25% of the potential flow of the NAS for iSCSI traffic.

• ISCSi LUN Vmware question

  I have two luins iscsi for vmware build hook etc. up to an emc celerra server.

  question-

  If I extend the iscsi on celerra lun in vmware puts it auto-mattically updated space iscsi LUN or is there more steps involved.

  Hello.

  There are more steps involved, after performing the operations on the Celerra.

  Use http://kb.vmware.com/kb/1752 as your starting point.

  Good luck!

• iSCSI Multipathing - really useful?

  Suppose to have this configuration:

  2 ESXi host-> HP DL380 G7 (4 x 1 Gbit NIC + 2 x 10 Gbit NIC)

  1 storage-> MSA P2000 (2 x 1 Gbit NIC + 4 x 10 Gbit NIC)

  The two hosts will be connected to the storage through 10 Gbit adapter. Since no 10 Gbit switch is available, guests will be DIRECTLY connected to the storage.

  Multipathing is always necessary in this case? I mean, I can understand, multiple paths is very useful if you have several path to reach the storage (multiple switch with a network different for examples). But in this case, if for example a 10 Gbit card on one server will be lost, I would therefore lost two way.

  Am I wrong?

  Is 4 x 10 GbE NIC on storing a single NETWORK card? Otherwise, you can cross the cables from hosts to it and have a warranty from the point of view of the moribund NIC storage.

  Since I read your post tos ay that the cards 2 x 10 GbE NIC on the hosts are a single card, and if storage 4 x 10 GbE NIC is also a unique card, while the only reason for multipath would be to have access to the additional uplinks to a higher throughput of iSCSI.

  I would consider using the 1GbE NIC as an uplink ensures 10GbE links to help prevent single points of failure.

• Gross storage iSCSI and VMDK questions

  I don't know if this is the best place for this question, so let me know if it is better to have another forum.

  I have ESX4 Setup on a server with a box of Equalogic serving 500g on iSCSI disks. For now, I have a 500 GB slice that I use only for the OS data and store all on OS VM.

  One of these virtual machines is a replacement for our mail server on Ubuntu 10.04 server that I want to run Zimbra. In our current setup, we have a physical 400 GB RAID 1 implemented as the/opt directory to store the install zimbra and the data store, this config partition makes I/O and backup issues a wink. I want to replicate this model, but I'm having problems.

  As I understand it, I have two options on the new VM server.  I can attach a raw disk via iSCSI via the menu vCenter as a connected virtual drive, or I can config the iSCSI connector in Ubuntu to access the drive directly.  I prefer the former because it makes things simple, but what I will meet an error when I try to connect the drive.

  Basically, it forces me to choose the location of the data store virtual and I have only two options, the 147 GB SAS on the physical ESX Server or the iSCSI drive 500 GB that I have attached to vCenter for the OS data. In both cases the error that I get States that there is not enough space on the data store for the extra 500 GB added to the virtual machine by attaching it.

  Yes, is there a way to add this iSCSI disk to the virtual machine without being part of the VMDK files? Or what I need to reach via iSCSI inside the Ubuntu VM? It would be nice to take advantage of snapshots and others, but I don't see how to do this job unless I have duplicate all storage making it OSdata drive big enough to accomidate the attachment of additional 500 GB to this virtual machine and even all my other virtual machines that have similar needs. This seems impractical because it would literally data duplicated without the benefit of the RAID or parallel I/O.

  Thanks in advance for any help/advice.

  We've covered this before, but you're absolutely sure that "OSDATA EQ iSCSI" is formatted with a block size of 4MB?

• iSCSI Multipathing vs just make the NICs active/active (vSphere)

  Hello

  I have 2 physical cards in my iSCSI vSwitch for dedicated and I understand that if I want to use multipathing I need to create 2 VMKernel ports, assign to each NETWORK adapter and connect them to the iSCSI initiator using the CLI interface.

  It is, what are the benefits this new management feature gives multichannel just teaming network adapters in an Active / Active configuration? The two configurations are not only as redundant ones than the others?

  Thank you

  Pete

  MPIO allows a server with multiple NICs for transmitting and receiving of I/O across all interfaces available in a compatible SAN corresponding MPIO.  If a server had four 1 GB/s network adapters and SAN had four 1 GB/s network adapters, the theoretical maximum rate would be about 400 MB/s (3.2 Gbit/s).

  Aggregation by grouping NETWORK adapters (or LACP, PAgP, 802.3ad, etc.) doesn't work the same way. Aggregation of links does not improve the throughput of a single traffic flow (a single source of communication with a single destination).  Only one stream will always travel the SAME path.

  The advantage of the aggregation of links is seen when several 'unique' streams (each with different source / destination) exist.  Each individual stream is sent down from its own available NETWORK adapter interface (computed by a hash algorithm).  Most unique feeds, most used network cards, more view aggregate throughput achieved. Aggregation of links will not improve throughput for iSCSI, although it gives a degree of redundancy.

  I hope this helps.

  Paul

• Problems with iSCSI Multipath i/o

  Hi people,

  I just started testing with ESXi 4 and hit a snag with the software iSCSI adapter and Multipath i/o.

  A bit of background reading, I understand that the storage architecture is a little different to 3.5, with the new PUBLIC service announcement.

  Anyway, here's the implementation.

  Single host ESXi 4.0

  -vSwitch1

  -Two cards of uplink physical

  -Two ports, with a VMKernel interface in each group (see attachment "Storage4 - Network.jpg'")

  -10.42.80.107 & 10.42.80.108

  -L' order of the adapter has been supplanted in the port groups while only 1 adapter is active in two groups of offices

  -Added the two interfaces VMKernel (vmk1 & vmk2) for iSCSI adapter, using the commands 'esxcli nic swiscsi.

  -Basically, everything described in the VMWare "iSCSI SAN Configuration Guide"

  Thecus R4500i iSCSI SAN

  -Two physical network adapters

  -Each physical NETWORK card has it's own IP address

  -10.42.80.200 & 10.42.80.201

  So in this configuration, I should end up with 4 paths:

  ESXi 10.42.80.107 - SAN 10.42.80.200

  ESXi 10.42.80.107 - SAN 10.42.80.201

  ESXi 10.42.80.108 - SAN 10.42.80.200

  ESXi 10.42.80.108 - SAN 10.42.80.201

  That is what I get, if I look in the "Configuration\Storage Adaptors\iSCSI software adapter" (see attachment "Storage2 - Paths.jpg'").

  But here's the problem, when I take a look in "Configuration\Storage\Devices\iSCSI Software Adaptor\Manage paths", I get only one path (see attached "Storage3 - Paths.jpg").

  Can someone help explain this? Did I miss something?

  This same configuration (servers, network cards, SAN, etc.) everything is perfect with multiple paths in ESXi 3.5

  (And Yes, I know that the Thecus ' "is not on the HCL supported, but we are only talking about standard iSCSI here, no additional Plugins storage, etc.)

  Not uber-urgent, but annoying, as this lack of multipathing would stop a vSphere deployment.

  Thank you

  Graham.

  Looking at the trace, it seems that, the table is not confirming to the specification when it sends data VPD. Let's not id NAA format. According to "spc3r23, 7.6.3.6.1 basic format of identifier NAA", the first Quartet of the NAA id can be 0 x 2, 0 x 5 or 0 x 6. However, the trace shows 0 x 9. ESX 4.0 does not have several paths to the LUN b ' cos of this. Is there a way to disable 'Page of Identification of device' on the side table.

• VLANS, DHCP, subnet, gateways and Multipathing Setup Question

  Hi, I have a House VI3 test network configured like this:

  Netgear wireless router,

  Adapter plugged into Port A1 of HP Procurve wireless game layer of 4000 M 2 switch with 802. 1 q (provides the uplink to my router upstairs that serves internet)

  VLAN by default 1 is 192.168.1.X/24

  On this switch, I have 2 ESX boxes with 4 cards each, Openfiler iSCSI target and a Windows XP Pro box running my Virtual Center.

  I have a Virtual Machine that running SBS2003 with also serves as my DNS server and my DHCP server.

  SBS2003 - 192.168.1.6

  Gateway (router Netgear) 192.168.1.1

  ESX1 - 192.168.1.10

  ESX2 - 192.168.1.11

  XP Pro - 192.168.1.50

  Well, with that of the road, my question is I want to set up a VLAN on my switch Procurve to separate traffic by default network, iSCSI and vMotions traffic.  By ESX Server best practices. to install a second Nic vKernel or SVC Nic console, they must be on a separate subnet with a defined gateway.  If I create a new vLAN for iSCSI and assign a network adapter, the network traffic will not be able to see my gateway. I also need my DHCP server to receive requests from any computer on any vLAN individual and issue a corresponding IP address.

  Now, what should I do?  If I create a vLAN Tirtiary or the second, I'm not able to see the DHCP server of these VLANS?  I can only UNTAG a port in 1 vLAN and port of marking abandon any connection to my DHCP server.  On this switch I assign IP addresses for individual VLANs, but this did not help.  DHCP isn't bradcasting across multiple VLANs. Am I missing a piece of hardware to provide ACLs or something?

  I don't know where to go from here, please help.

  Hello

  To route between VLANs, you must be a switch of layer 3, is a router configured as "a router on a stick", which is essentially a port of the switch, configured as a trunk, connected to the router that is configured with a number of interfaces, one for each VLAN so that it can route traffic between the VLANS. Now create a VLAN for VMotion traffic is fine as has no need to be routed. The VLAN for iSCSI and VLAN to the Service console will have to be sent to iSCI work properly. DHCP can work through several VLANS but need aid IP to be configured on the switch.

  Concerning