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11

I believe that it probably has more to do with legacy then it does moving forward. Despite the fact that A and B were taken and C became the default hard drive assignment, most applications assume that C is the default OS location, A and B are floppies, and D is CDROM or DVD drives. I've seen applications break if the default OS is not located on C.


9

On a modern system, a partition device will only appear if the partition actually exists. On a disk with an MBR partition table, partition numbers 1 through 4 correspond to the four slots in the partition table, called "primary" partitions. They don't have to be filled sequentially, so it's possible, for example, to have an sda2 but no sda1. Partition ...


7

Some (badly written) software, including parts of Windows assumes that the OS drive will be C, and will crash/fail if this is not the case. Microsoft doesn't want to break stuff, so they've left the default as C.


6

There is no backup.. This is the problem. Storing important data (on ANY system, no matter how reliable) without a backup is indeed the problem! Having no backup, and having experienced a failure mode for RAID 5 for which there is no proper recovery path, you are now what our British friends would refer to as "Right Royally Rogered" (actually they would ...


6

WDC Green drives have the "deep recovery" problem. You'll need Red or RE drives to avoid it. I have a ZFS RAIDZ of Green drives at home. They've lasted almost 3 years of Power On Hours without a single error. This may be just lucky, but errors don't generally happen all that often. So you have to ask, is the cost difference worth it. Take the value of ...


5

There are only a limited number of drives that are certified - non certified drives wont be recognized by the array and will not work even if they are otherwise identical to the drives already in the array. For SATA drives you will also need an interposer that allows the MD3000i controller to interface with the SATA drives. If you can precisely match the ...


5

My own experience with other vendors has been that they will swear up and down that other drives won't work...then, of course, I tried it, and it worked fine. Of course, if this is for enterprise usage, you should not use your own. The reason is that the drives that they sell (with the high markup) have specific firmwares that disable disk caching, and ...


4

As far as I know, when the kernel detects a new block device on a scsi-like (incl. sata) bus, in addition to adding a node in /dev for the whole disk itself, e.g. /dev/sda it will attempt to see if there's a partition table. If there are readable partitions, it will then create the partition nodes numbered depending on whether they're physical or logical ...


3

Never use raid 5 on slow disks, and never use it on software raid. Also never use it unless you have a decent raid card with its own cache and pre-failure analysis.


3

I just wanted to update everyone on the solution. End result i got all my data back except for 2 files and here is what i did Installed the good drive and the drive that failed during the rebuild Forced mdadm to create the array with 1 drive missing and set the flag so that all disks are clean used MC (midnight commander) to start copying files folder by ...


3

You can't shrink those arrays, only grown them, I don't know why you think it may be possible. HERE's the quickspecs showing what can be done.


3

It is not possible. Please see: Is it possible to shrink the size of an HP Smart Array logical drive?


3

I've used two. DoubleTake is a common one for applications that don't have much disaster recovery capabilities built in. Veritas Volume Replicator is a really slick enterprise-quality one. I've seen that used with Microsoft Exchange, for example, to replicate data between two different SANs. If I had to recommend one over the other, it'd be Veritas.


2

If the unit is still under support, the replacement drives are free. Call Dell and they will send out someone with a new drive (time will depend on your support agreement). I've done this a few times with our SAN that we bought from Dell.


2

Might work, but not supported. If you run into trouble, the dell tech will demand you remove everything non-Dell provided from the MD. And without those disks a disk array is not usable, and troubleshooting is not possible.


2

David, the text provided on Dell's website only indicates that you can mix SAS and SATA drives that are purchased from Dell within a given PowerVault chassis. It does not mean that you can use non-Dell drives in this unit. The License Agreement that accompanies the hardware details this limitation.


2

When I built my last home machine using Vista, I tried to use A: & B: for the CD-ROM drives. I forget all of the problems with that I encountered, but Vista was clearly not amused.


2

I work for a major hosting company, and the most common thing I see in my enterprise segment (not necessarily that I recommend, but what I see), assuming that the server is standalone / using local storage, is a RAID 1 OS array, and a RAID5 data array. Now, as hard drives get bigger, RAID 5 really becomes less ideal, as your likelihood of hitting a URE ...


1

I have seen this happen in external enclosures when they are not receiving enough power. Using first generation USB this happens quite often. You might want to use an external power supply + the enclosure I know - not quite as easy as it should be.


1

You can boot from ubuntu CD into recovery mode. Then, you can execute a root shell. Look for your drives using: # ls -l /dev/disk/by-uuid/ You should get symlinks to your actual drives such as /dev/sda1 and /dev/sda2. Look at /etc/fstab and compare the UUID you found there with UUID you got from ls. You can edit the fstab accordingly. You can try to ...


1

I'm okay with the primary disk being C:, but I'd like my flash drives to be seen (by default) as A: & B:. At least they would have purpose again! -JFV


1

MD3000i only accepts DELL certified disks. There is not secure way to add thirf party physical disks even with same model because the firmware is owned by DELL (both SAN and disk).


1

I implement this by running Windows in a Xen VM under Linux (CentOS) and using DRBD to mirror the VM's disk images. Okay, so it's an extra level to figure out, but it is free and gives you the flexibility to start adding further VMs to your machine. I also use Linux LVM to make easily resizeable disk volumes to use as VM disks. Hardware wise, other than two ...


1

There are several options. DFS-R is built into Windows 2003 R2 and 2008 (and I use it) FRS is built into 2000 and 2003 R1, but I wouldn't recommend it. These are really aimed at file shares and are file-level mirrors, not block-level. If you have a disk that you want two servers to see, then you need windows clustering, but you need a hardware base for ...


1

Just because there is no reason to change. Changing from C to A can only break things and doens't do anything working better. Most application wouldn't have problem to run even if C: is not the system drive but you may have custom scripts running on your server with hard path to some file (exemple if you have a software to analyze apache log file) and if you ...


1

I've used other drive letters like D: for my Windows partition (and then A-C for data partitions) since Windows 2000 without a single problem so this is just tradition. If there's some software that won't handle it, I haven't seen it...


1

Why change? What advantage would it give? Something like this needs a reason for change and so far nobody has come up with anything that would warrant such change. As for dropping the use of drive letters altogether, the same argument applies. There are pros and cons both ways, with neither being a clear winner.


1

Find out what's using the disk space! Is this a mail server? Log server? It's entirely sensible in that case. The tool xdiskusage is great for visualizing disk usage in scenarious like this.


1

/dev/sda - raw device /dev/sda1 - 'virtual' device, like a partition. One interesting difference is that if a device has partitions (has MBR data or sth alike) you can't read MBR data from any of the virtual devices, as MBR data resides outside of any partitions on a device. MBR resides in the first sector of the device (CHS: 0 0 1). There is a good ...



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