Virtual disk or a raw device

Similar Questions

• 11g RAC - RAW Devices Configuration

  Hello
  
  Please let me know if there is a difference in the configuration of RAW devices for 11g RAC compared to 10g.
  For example in 10g, we would separate RAW Devices for OCR, voting disk, ASM spfile, archives log files and database files.
  
  Please let me know if configuring RAW devices in 11g is different from that of 10g.
  
  Kind regards
  N V
  
  Published by: user7202581 on April 19, 2011 23:54

  Hello

  all first with 11.2. directly use the RAW devices is no longer supported. However, you can use RAW devices below ASM. So if you use ASM for data files, archivelogs etc, then the ASM disks can be RAW devices.
  Second: A general comment on Linux RAW devices. Have become obsolete from CRUDES Linux devices (I think with RHEL 5.3), so I recommend the direct use of block devices (which is possible since 10.2.0.2).

  No to your question:
  With 11 GR 1 material has not changed the configuration of the CRUDE devices.
  With 11 GR 2, the configuration has changed. See the Grid Infrastructure Installation Guide for additional and accurate information (on the installation, rights of user etc.).

  http://download.Oracle.com/docs/CD/E11882_01/install.112/e17212/storage.htm#CDECEBGH

  Concerning
  Sebastian

• Best practices - virtual disk of Raw device mapping vs

  Hello

  A small question about the configuration. What would be described as the best practice to configure a comment server that required a large amount of disk space? What is the preferred option:

  1 - create a virtual machine with a mapping of raw device to the LUN (on a san)

  or

  2 - create a virtual machine with another large virtual disk that is in a data store on the LUN (on a san)

  Thank you

  Dave

  Kader you are limited with 2 TB in any case (except using the iSCSI software from within the guest operating system), the only arguments are:

  (1) use RDM if it is possible that you will connect to this physical machine LUN. Or you already have the unit number logic of a physical machine as a large file server.

  (2) VMFS use in all other situations - VMDK give flexibility, you can migrate the virtual machine where you want.

  ---

  MCSA, MCTS, VCP, VMware vExpert 2009

  http://blog.vadmin.ru

• RAW device to the virtual disk migration

  When trying to cold migrate a raw disk device VM of EVA Storage to a virtual disk in a DS8100 it fails with the following message: "incompatible device backup specified for device ´0´" the size of the LUN is Go 510 and appaers message when 100% is full 3 hours laters. I set the block size 2 Mb in the data store, but when I try to migrate a RAw of 100 GB on the same VM migration works very well and I use the new virtual disk without problems.

  This could be a problem with the maximum of storage migration?

  Could you tell me if you know another way to migrate this raw device on the virtual disk?

  TKS!

  Have you tried VMware Converter inside the guest who has the backend RDM?

  Jase McCarty

  http://www.jasemccarty.com

  Co-author of VMware ESX Essentials in the virtual data center

  (ISBN:1420070274) Auerbach

  _{Please consider awarding points if this post was helpful or appropriate}

• [Performance] Data store Virtual disk LUN or a raw device

  We try to find the solution the faster for one of our internal systems.

  Currently, we have a data store that is located in a SAN iSCSI via a virtualdisk file.

  Since we want to benefit the maximum of iSCSI SAN configuration, we want to know what solution is faster:

  -Via the data as virtual disk (diskfile) store

  -Via direct LUN mappingl (mapping RAW)

  I searched the documents, but it is impossible to find the figures/numbers how much performance gain, we would be able to get.

  Us don't use clichés (and do not use then as well), and what other pinpoints should I also everything by making the decision to change the architecture?

  There may be some performance improvements, you can do in your env, but they come from VMDK of RDM.

  -Matt

  VCP, vExpert, Unix Geek

• Virtual Raw Device Mapping

  Can someone explain to me the difference between a regular virtual disk and a virtual raw device mapping? When I create the RDM I am just creating a file pointer to the correct virtual file? If yes why anyone would use virtual raw device instead of just mapping to create a typical virtual drive? I understand the benefits and limitations of the physical RDM I just do not understand the goal of the RDMS virtual.

  Well, even if a RDM in virtual mode allows you to use the tricks and VMware snapshots is not always the same thing as VMFS datastore.   As stated previously, you can easily remove this ROW and the provision of a physical server without losing a bit of data or to copy.

  If you have found this device or any other useful post please consider the use of buttons useful/correct to award points

• RDM (Raw Device mapping) physical or virtual?

  Hello:

  I have VM and will add a hard drive.  RDM will be, but I was wondering what "Compatibility Mode" choose "physical or virtual?

  It's my production Oracle machine and this new drive will contains about 500 GB of DATA...

  I think it would be nice to use the 'virtual' mode, to make snapshots, but I'm worrying that, for this one big disk, it will take a lot of time and a lot of space... There are other arguments that I should consider?

  Thank you very much.

  Best regards

  olegarr

  olegarr wrote:

  Surya,

  Thank you very much for your help.

  What is any other reason to use Virtual Mode, if I used instant no?

  Thank you

  olegarr

  "design of the SAN and Deployment Guide system.

  Virtual mode for a mapping specifies full virtualization of the mapped device. He

  appears to the operating system exactly the same as a virtual disk in a file

  VMFS volume. The actual physical features are hidden. Virtual mode

  customers who use raw disks of the benefits of VMFS, such as advanced files

  locking for snapshots to streamline development and data protection processes.

  Virtual mode is also more portable across storage than the physical hardware,

  with the same behavior as a virtual disk file.

  Physical mode for a device mapping gross specifies the SCSI virtualization minimum of la

  device mapped, allowing greater flexibility for SAN management software. In

  physical, VMkernel mode all SCSI commands to the device, with a

  exception: the REPORT LUNS command is virtualized, so that VMkernel can isolate the

  volume to the virtual machine owner. Otherwise, all the physical characteristics of the

  underlying hardware are exposed. Physical mode is useful for running the SAN management

  agents or other software SCSI target on the virtual machine. Mode of physics

  also virtual and physical memory allows for cost-effective high availability clustering.

• Virtual Disk Manager "the device is not ready".

  I don't know about the format from outside, possibly MAC OS EXTENDED. He was not ejected a Mac and will not mount on an operating system MAC or PC (Windows 7 Professional) using Firewire (800 to 800 and 800 to 400), eSATA and USB 2.0. When I use disk management, disk will appear as not initialized and next to the "disk 33", there is a red arrow pointing down. Whenever I open the Disk Manager, the window to initialize the disk appears, but once I chose a style of partition and press OK, the virtual disk manager pops up saying "the device is not ready". I also tried to wipe the drive using CMD, (disc of DiskPart/list / select disk 33/clean), CMD said the drive was clean, but when I went to disk management, without change.

  I'm looking for a way to clean the drive so that it can be reformatted and reused.

  Hi Catherine,

  The question you posted would be better suited in the TechNet Forums. I would recommend posting your query in the link below.

  http://social.technet.Microsoft.com/forums/Windows/en-us/7e214b16-E415-449a-8f25-4cace51e5106/Virtual-Disk-Manager-error

  Good day!

• There is no more space for virtual disk by turning on POS device.

  

  NOTE: After 2 days to schedule a daily backup of a critical server, WTP device is off and throw the foregoing pushed error while it turn. I understood that VDP device disk space is less than the amount of data backup pd. kindly suggest me how to overcome this problem.

  (physical host 3 + 1 environment SAN, VDP is located on one of the host's local storage physical there not on the SAN)

  looking for your kind suggestions/solutions.

  Kind regards

  Alaka

  ... VDP is located on one of the host's local storage physical there not on the SAN

  According to the error message, local storage of the physical host has run out of disk space due to unit VDP growing (thin provisioned) data disc "Data Protection 6.0_1.vmdk". Backups require more than currently available disk space, so there is not a lot of options available. You must either increase the data store to which this virtual disk is stored, or migrate to another, more department store of data if you want to continue to run backup jobs as they are currently configured.

  André

• Migration of raw device to VMDK virtual card reader

  Hi all

  I currently have 3 5.0.0 ESX 504890 hosts.  I have about 12 people who unfortunately have mapped drives of raw device.  I would like to convert VMDK to a data store.  I have VMware Standard, so I vMotion and Storage vMotion at my disposal.

  I tried a migration of guests which has a hard drive of the RDM.  Steps are the following:

  1. Right-click on the client
  2. Select migrate
  3. Select change Datastore
  4. Click on advanced
  5. Select the data store that I want to spend.
  6. Select thin provision
  7. Click next

  Once it's over it's now a VMDK created in the data store but when I go in the settings on the guest he always shows as RDM.  I'm doing something wrong here as the VMDK which was create shows, it has been changed at the end of the procedure.

  Thank you for taking the time to read/post on my question.

  

  

  Just to confirm. You have selected different datastore to where you want to migrate the virtual computer?

  André

• RAW Konvertere til virtual diske diske

  Skal I gang med at konvertere / flytte mine nuvaerende til virtual diske, men jeg smarter det gar how LUN?

  Det er the fordi har dinner RDM I physical Mode... SA the ikke kan wash en konvert sVmotion hav...

  / Rubeck

• RAW Device Mappings is grayed out

  Hello everyone.  I'm a noob EXSi/VMware, so I'm a little out of my comfort zone.  I have a Supermicro motherboard with an onboard SAS controller which is supported in EXSi 6.  I have eight 4 TB drives, attached to the SAS HBA and 2 connected to the integrated SATA SSDS.  I was able to add all readers as warehouses of data and that works very well.  But I need to devote several full discs on a virtual computer and I have not been able to get this working as RDM option is grayed out any virtual machine, I try.  Tried to remove one of the hard drives for data warehouses (missing) but I still don't see it as an option (and now I can not see it when I try to add back as a data store but that's another issue).

  I did research on this question and I tried to disable the RDMFILTER option in the advanced settings and no go.  I tried to run the process in article KB 1017530 (Raw Device Mapping for Local storage, I get the following error:)

  vmkfstools - z/vmfs/devices/disks/t10. ATA___TS32GSSD25S2DM___201009163653400631A4:9 /vmfs/volumes/APPSSD/RDM/rdm9.vmdk

  Unable to create the virtual disk: the system cannot find the specified file (25).

  I thought that I needed to create the folder ROW in the store, so I did and then I got a new message:

  Unable to create the virtual disk: operation not permitted (65545).

  Any help would be greatly appreciated, thank you!

  You have created the file pointer correctly!

  # vmkfstools - z/vmfs/devices/disks/t10. F405E46494C4540046F455B64787D285941707D203F45765 /vmfs/volumes/Datastore2/localrdm1/localrdm1.vmdk

• How to find the logic of a RAW device unit ID-number

  Hello

  I am trying to create a workflow that will give me information about a virtual machine:

  • RAM
    
  • CENTRAL PROCESSING UNIT
    
  • Disk configuration
    
    • Size, SCSI Bus
      
    • ..
      

  My problem is to understand the LUN ID to a RAW device in a virtual computer.

  I think, a RAW device is listed as the VcVirtualDisk type too?

  Anyone know how to determine the LUN ID of a RAW device?

  Thank you

  Marc

  Hello!

  This should help you:

  http://communities.VMware.com/message/2012069

  See you soon,.

  Joerg

• How to migrate VM from\TO Raw Device Mapping (RDM) (data store)

  Hi all

  I have aske on the migration of VM from\TO Raw Device Mapping (RDM) (data store)?

  Thank you all for your support

  If you are using vSphere 5, then you can SvMotion the VM attached to a RDM (physical or virtual) with no problems. This means that only RDM mapping file will be moved to another data store without any conversion of changes on the real disc of RDM.

  Note: Do not attempt to change the format of disc thin or thick, which would cause the RDM disk converter for virtual disk.

  More info here: http://blogs.vmware.com/vsphere/2012/02/migrating-rdms-and-a-question-for-rdm-users.html

  If vSphere 4.x is used, hot and then migrate the virtual machine to another store of data will not change the format of the ROW, only mapping file will be moved. This is true for virtual and physical RDM.

  However, the cold migrate the virtual machine to another Datatore will change the ROW to virtual disk format.

  HTH... Let me know if you have any questions...

• Grey raw device mapping

  We are implementing vsphere 5. our host machine is HP DL 380 G7 and storage storage IBM DS. We are implementing SAS SAN using HBA cables. There is no iSCSI or fiber module. We want to implement file on vphere server using win Server 2008 R2 SP1. We want to access our data directly from SAN LUN and not vmware data store. Whenever we try to add disks of virtual machines, raw device mapping is gray. If we check in the adapters of storage, we can see available LUNS. I don't add it to the data store. still, it is grayed out. Why? Please help us

  Welcome to the community,

  Please read http://kb.vmware.com/kb/1017704 to find out if your storage system supports the RDM and whether it's save to disable the ROW filter. Article is not tagged for ESXi 5.0, but I guess this also applies.

  André