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Questions[raw-disk](server)

Martin Hope
Yves Martin
Asked: 2016-09-21 04:55:05 +0800 CST
  • 7

I try to setup DRBD on a raw disk device /dev/sdb without partition table, nor LVM stack PV/VG/LV

As this disk is virtual and hypervisor I use allow on-the-fly disk extension, I do not want to bother with LVM operations or re-partitioning when comes time to extend my DRBD file system

My resource definition cannot be simpler

resource data {
  device  /dev/drbd1;
  meta-disk internal;
  disk    /dev/sdb;
  on node1 {
    address 10.10.10.16:7789;
  }
  on node2 {
    address 10.10.10.17:7789;
  }
}

Create metadata works

# drbdadm create-md data
initializing activity log
NOT initializing bitmap
Writing meta data...
New drbd meta data block successfully created.

But attach operation fails

 # drbdadm attach data
 1: Failure: (127) Device minor not allocated
 additional info from kernel:
 unknown minor
 Command 'drbdsetup-84 attach 1 /dev/sdb /dev/sdb internal' terminated with exit code 10

Error message really sounds like command expect a partition table index as device minor code.

How should I attach a raw device to DRBD resource ?

drbd raw-disk
Martin Hope
user462982
Asked: 2011-10-24 10:48:43 +0800 CST
  • 3

Is there some program for windows that is able to do what dd does in linux out of the box? I need to copy from a file to a physical disk in raw mode where I need to define offsets for input and output. So for dd, I'd need to use the seek and skip parameters. I know there is (1) http://www.chrysocome.net/dd or I could try to (2) setup dd using cygwin but:

  1. Does multiply the skip parameter with 512 (which I believe is wrong). I want to skip=4198399 sectors but it then tries to skip 2149580288 sectors (bs=512). So with this bug, the program is useless for me.

  2. I tried to use dd under cygwin as partially decribed here: http://cygwin.com/ml/cygwin/2000-08/msg00885.html. I did this

    mount -f //./physicaldrive0 /dev/enc
mount -f of=/dev/enc if=/cygdrive/f/inputfile.dat skip=4198399 seek=4209089

and got

dd: opening '/dev/enc': Invalid argument"

Similarily

    mount -f //./Device/Harddisk0/DR0 /dev/enc

resulted in

     dd: opening '/dev/enc': No such file or directory"

So I am tired of trying with cygwin.

Are there other programs/options that could accomplish a dd kind of raw copy (maybe some disk editor)?

Thanks

windows cygwin copy dd raw-disk
Martin Hope
Matt Simmons
Asked: 2010-06-30 11:30:52 +0800 CST
  • 3

I'm building VMs in my lab and I want to replicate the situation that my fileservers will be encountering in production. Here's a brief overview of what I want to do.

I have multiple ESXi 4 servers. They are accessing a SAN, and each virtual machine will exist in its own LUN on the array. I also have LUNs which house data that needs accessed by the VMs.

My goal is to have a VM (lets call it fs, for fileserver) started on VMhostA. I want fs to be able to access a data LUN in raw mode, meaning that if fs goes away, I want to be able to mount it as ext3 (or whatever) from a physical (non-virtual) machine. This means that the data on the LUN must not be housed in a vmdk file. In addition, I want to be able to use VMotion to move that VM to VMhostB (and obviously, maintain access to the data LUN)

It is my understanding that I need to present the LUN as a Raw Disk Mapping (RDM)? From what I have read, the RDM file created can be stored with the fs virtual machine or on another datastore. Would it be correct to assume that it should be stored with fs?

Also, there exists two types of RDM, it seems. There are physical and virtual modes. I have encountered conflicting documentation from various sources, so I'm not sure what to think. Does it matter which I select in this case? What are the differences, as they apply to my situation?

Thanks very much for reading all the way through ;-)

virtualization storage-area-network vmware-esxi raw-disk
Martin Hope
Rob
Asked: 2008-11-20 00:18:57 +0800 CST
  • 5

I have a Windows 64-bit host running VMware Server 2. I need to create VMs that will use the raw partitions for my Linux and Windows XP installations. Older versions of VMware had an option to add a raw disk, but VMware Server 2 only allows me to add a physical disk via the wizard.

If I was running a Linux host, I'd create a SCSI pass-through device, but when I try this in Windows the other partitions don't show up (only the CD-ROM shows up as a SCSI device).

How can I access the raw disks in VMware Server 2 on a Windows host?

EDIT: There is an unsupported method of adding a raw disk on a Linux host by editing the .vmx and .vmdk files. On Windows hosts, people have reported being able to import existing virtual machines which have raw disks, so it seems that the capability still exists but is no longer exposed by the UI. I'm wondering if anyone has gotten the unsupported method to work on a Windows host. I've tried, but haven't been able to get it to work.

vmware-server raw-disk