Hi Anna: On Thu, 3 Oct 2002, Anna Schneider wrote: > First, I did get a couple of tutorial, I think they are tutorial, Red Hat > CD's with my system, but I don't know how to access them. I have to do > something with mount don't I, but I do I know what I'm mounting, and how > do I know which device is designated as what, and once I get the CD > writer/reader mounted, how do I read the information it has? OK. First, to mount a device, you have to be root. Second, you need to find out what device you need to mount ... unless you've already found out. check in /etc/fstab to see if there's an entry that looks like this: /dev/cdrom /cdrom auto defaults,noauto,ro 0 0 If you have, then mounting will be easy. All you'll need to type is: mount cdrom and it'll mount it on the stipulated mountpoint (in this case, /cdrom). If you don't have a line like this in your /etc/fstab file, you'll need to do a bit more investigation. 1. Determine which device is your CD ROM. If you know already, skip to number 2. First, see if you have a device called /dev/cdrom. This is usually a link to the proper device name that's used for convenience. Type the following to check: ls -l /dev/cdrom If you get something like: ls: /dev/cdrom: No such file or directory Then you don't have a /dev/cdrom device. If you do have one, you'll get something that looks like this: lrwxrwxrwx 1 root root 8 Nov 7 2001 /dev/cdrom -> /dev/hdb You don't need to take a note of the /dev/hdb or whatever it's linked to, since you'll be able to use /dev/cdrom to refer to it. If you don't have a /dev/cdrom link, we need to look still further. Type: dmesg |more Here you'll see all that stuff you hear at boot-up which tells you a lot about your system. Look for lines like this: hdd: ATAPI CD-ROM DRIVE 24X MAXIMUM, ATAPI CDROM drive and hdd: ATAPI 20X CD-ROM drive, 120kB Cache hmmm. They;re a bit contradictory. ah well. Anyway you'll notice the hdd at the front of the line (can you tell this came from a different machine from the first example?). hdd is the device name for the CD ROM. Depending on your setup, it'll either be something like HDA through HDD, or SCD0 or something. NOTE: If you don't see anything like this at all in dmesg, then chances are that your CD ROM is not being identified and if so, none of the below is going to help you at all. 2. OK, we've figured out what device the CD ROM is. Now what? Ok, to mount a filesystem, you need both a device to mount and a place on which to mount it. Most distributions have directories set aside for this sort of thing, like /mnt and /cdrom. but you can call them whatever you want. Just so long as it's an empty directory somewhere. I'll use /cdrom as it's convenient and says what it is. To mount your CDROM, ensure you have a data disk in the drive, then type: mount /dev/hdd /cdrom Substitute hdd for the device name for your cdrom device. And yes, if you have a /dev/cdrom link then by all means use that. Providing all went well, you'll be returned to your command prompt. At this point, you'll now have the contents of the CD available under your mount point. so if there's a file called README in the root directory of the CD, it'll be listed as /cdrom/README providing you mounted it on /cdrom. to explore it fully, you'll probably want to cd to the directory you've mounted the CDROM on and use ls and such to see what's there. While the CD is mounted, you won't be able to eject the CD. So you'll want to unmount it at some point. to do this, make sure you're not in any of the directories being used by that device (i.e. if you've mounted it on /cdrom then make sure you're not in the /cdrom directory or any of its subdirectories). then type: umount /cdrom or whatever the mountpoint is you've used. 3. OK. I had to go digging for the devicename and now I can mount and unmount my CD using it. But you referred to some conveniences to make this simpler? Yes. If you don't have a /dev/cdrom link to your CD device, you can make it by, as root typing: ln -s /dev/hdd /dev/cdrom Of course, if your CD ROM is another device then type that instead of /dev/hdd. This is a good thing to do as many programs look for /dev/cdrom when wanting to use the CD ROM device. If you do this, you'll be able to type commands like: mount /dev/cdrom /cdrom If you want to be able to just type "mount /cdrom" then you'll want an entry in /etc/fstab. Mine looks like this: /dev/cdrom /cdrom auto defaults,noauto,ro 0 0 You can probably just cut and paste this example if you want to mount it on /cdrom. Just before I move on. I've listed a number of things you need to do as root, and there'll be more further down. Remember when you're root, most of the safety features are over-ridden. So it's vital that you make sure you've typed commands correctly before you run them, as if you mess up it might be difficult to undo. > second, I'm still having modem problems. I can dial in with ppp okay, but > then I can't seem do telnet or ssh, and I don't know where their config > files are, or their how-to files. I means I've skimmed the info pages on > them but it's all jibberish to me. When I try ssh, I get something about > host name resolution failure, and telnet just can't find the host. Now, > from my non-ppp account on Drizzle, I often telnet to the catalog ofr the > Washington Talking Book and Braille Library, and that works fine, but when > I even tried doing that on my Linux machine, I couldn't. It couldn't find > it or something, but I'm wondering if it's actually a problem on my end. It is. As you may have guessed, your linux machine is unable to turn the host names you give it into IP addresses. This is because it is probably not configured to ask a DNS server about it. There's a couple of ways to deal with this. The simplest way is to get the IP addresses of the DNS servers your ISP uses and put them in /etc/resolv.conf like so: nameserver 61.9.208.14 nameserver 61.9.208.15 nameserver 61.9.192.15 You may need to ask your ISP for the addresses, but since you have a shell account on your ISP, then you can probably find out yourself what their DNS servers are. Since many programs need to be able to read the resolver file, try typing (on your shell account): cat /etc/resolv.conf I just tried it on a shell I use and I can do it. this will make life easy for you as you'll be able to cut and paste the nameserver entries from their file into yours. Of course, you'll need to connect to your shell account while in LInux to do this, but if you can get the IP address of the host machine then you should be able to telnet to that IP address since it won't need to be looked up. Many ISPs configure PPP to tell your machine the addresses of their DNS servers automatically. As you will have seen on the speakup list, there's a few ways to deal with this and I think different distros do different things. I like the scripts that Debian has, and will probably even post them to the list for others to grab if they wish. If you want to get tricky and run your own DNS server, either to just cache DNS results or even provide names to other computers on ;your network, you can do so, though this is a bit of an exact science and is a whole new area to research. > This doesn't make any sense does it. I can't do anything. Every time I > try I go backwards. I don't understand the the info pages because they > are so terminology ladend. I can't find help on the things I need because > I don't know where to look. OK. No it does make sense. The info pages are more a source of reference than anything else, which is why they can be cryptic. A good place to get some help is the howto documents at the linux documentation project at http://www.linuxdoc.org. They can also be a bit presumptuous about what you know, and they nearly always tell you how to do things without reference to any conveniences your distribution might have. So you might want to also do what you've already done, ask questions here. > Oh, and I can only access my moem as root, not > as anther user and I can find where to change that because I don't know > what to look for. I'm guessing this is because you don't have permissions to access your serial port. Usually distributions have a good access structure built into them, so it's easiest to just go along with it. So look to see the permissions on your serial device. If your modem is on ttyS0 (com1) type: ls -l /dev/ttyS0 If your modem is on ttyS1 (com2) type: ls -l ttyS1 Note the capital S in both examples. I'll show you what mine looks like: crw-rw---- 1 root dialout 4, 64 Jun 13 2001 /dev/ttyS0 Now, you'll see that both root and the dialout group have read and write permission on the serial port. so you want to put your user account in the dialout group. Edit /etc/group and look for the line with dialout. It'll look something like this: dialout:x:20: Now, add your account to the group by putting it at the end of the line (no spaces). So mine would look like this: dialout:x:20:geoff If I wanted more than one user in a group, I'd add them to the end with a comma seperating the names like so: dialout:x:20:geoff,anna Once you've done this, save the file. Changes will not take effect until you log your user account in again, so if you're already logged in as the user account, logout and log back in again. If you ever want to see what groups you're in, type "groups". Note that PPP is a bit complex and it might take a few group additions to sort out all the permissions. But you don't want any old user to be able to fiddle with the PPP link, do you. > Can anyone sort through this and give me pointers. This is starting to > throw my life into chaos. I hope I've been of help. Since you're used to shell accounts, you're one step ahead of some. Let me know if I can be of any further help. Geoff. -- Geoff Shang <gshang at uq.net.au> ICQ number 43634701 Make sure your E-mail can be read by everyone! http://www.betips.net/etc/evilmail.html Please avoid sending me Word or PowerPoint attachments. See http://www.fsf.org/philosophy/no-word-attachments.html
