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After successfully installing Ubuntu Server 12.1 from an ISO on a cd. Now the problem is this: Cdrom can be located manually, how ever it says that the DIR doesn't exist. I get this:

root@PXE:/dev# cd /cdrom/

-bash: cd: /cdrom/: No such file or directory

I know where the CD is, but we can not CD into the DIR. We are trying to set up a DHCP server on a dell poweredge R210. THE DHCP is working.

However my only issue is that i can not get Ubuntu Server to recognize the CDROM to gain access to ONE file i need which is pxelinux.o

If you need more info let me know.

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Maybe stupid question, but is de CD mounted ? – thom Nov 6 '13 at 2:21
Yes it looks like you are in the /dev directory and are under the impression that you can access the contents of the CDROM by cd'ing to /dev/cdrom (which would be cd cdrom by the way - no leading / before the cdrom) - that won't work, since /dev/cdrom is the raw (unmounted) block device. – steeldriver Nov 6 '13 at 2:41
Alright so I managed to get it to mount, however I'm facing a new problem. root@PXE:~# mount /dev/cdrom* /media/cdrom mount: block device /dev/sr0 is write-protected, mounting read-only I'm at a lose as to how to make it read-write. If it helps the server is a Dell PowerEdge R210 ii. As its pretty apparent that I'm a little newbie. Thanks by the way, you got me past my previous problem. – user212111 Nov 6 '13 at 18:37

In Linux, devices must be mounted to a location in the filesystem before they become accessible for reading or writing. In the case of Ubuntu desktop editions, CDROMs are typically automounted, but in the case of the server editions they must be mounted manually. The general format for that is

mount [-fnrsvw] [-t vfstype] [-o options] device dir

where device is the block device (typically /dev/cdrom for CDROM devices) and dir is the filesystem location where you want the device to be mounted (the mountpoint). In the case of CDROM devices, the vfstype (filesystem type) should be detected automatically, and other options are probably not needed, so it should be sufficient to do

sudo mount /dev/cdrom /media/cdrom

so long as the mountpoint /media/cdrom exists - if not you can create it with

sudo mkdir -p /media/cdrom

You will then be able to access the CDROM contents by going to /media/cdrom i.e.

cd /media/cdrom

Of course you are free to mount at /cdrom instead of /media/cdrom if you prefer.

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