Best of Technical Support

Our experts answer your technical questions.
Partitioning

I am installing and have a 3GB hard drive. I am not sure of the best way to partition it. Any suggestions? —Jes, jes2@mindspring.com

You do not say what you plan to do with the disk, or what the host machine is (server? workstation?). Personally, I usually partition as such:

/       (about 50Meg)
/safe   (same size)
/var    (half the space left)
/usr    (the other half)

I then link /home to /var/home and /tmp to /var/tmp/tmp. /safe is a copy of my root partition so that I can boot on it with LILO if my boot partition becomes badly damaged, and it also gives me a copy of my configuration files in /etc.

Adding more partitions can be nice, but the more you add, the more chances you have to run out of space in one of them. For instance, I think making /tmp a separate partition instead of linking it to /var is a stupid idea, unless you're willing to give it several hundred megabytes, or even a gigabyte, because some programs can create huge temporary files and may fail in bizarre ways if your /tmp partition is too small.

/usr is also meant to be read-only, which works very well on Debian and works mostly on Red Hat (they have incorporated most of my bug reports). In both cases, you'll still have to remount the partition as read/write before installing a package, however. —Marc Merlin, merlin@varesearch.com

Networking Oddities

I have tried to install Red Hat 6.0 twice now from the CD included in Sams' Red Hat Linux 6 Unleashed, and both times have run into the same problem. Installation goes fine, and when done, I can log in at the console with no problems, I can telnet out, ping, etc., and I can ping it from other machines on my internal network. When I use telnet to log in to the machine, I get “telnet: unable to connect to remote host: Connection Refused”. When I try to do the finger command, I get the same error. When I use FTP to get to the machine from a 95 workstation, I get “Refused”. When I try to do the finger command, I get the same error. When I use FTP to get to the machine from a 95 workstation, I get “ftp:connect :10061”, and of course, it does not connect. On this machine, the IP address is 189.0.1.50, and the subnet address is 255.255.0.0. Interestingly though, Apache does work, and I was able to connect the Samba client to the Samba server, so TCP/IP seems to be working, but only some services.

My inetd.conf file has the lines

ftp stream tcp nowait root /usr/sbin/tcpd in.ftpd\
   -l -a
telnet stream tcp nowait root /usr/sbin/tcpd\
   in.telnetd

Further down, I also uncommented the line

finger stream tcp nowait root /usr/sbin/tcpd\
   in.fingerd

I have used Red Hat and other Linux flavors for over two years, and have never had a problem like this before. —Charles Almond, charles@ovis.net

I answered a similar question for a local user who had exactly the same problem just last week. Make sure your inetd daemon is actually running. All the file changes in the world do nothing if the daemon isn't present to read it. You can do a ps ax and scroll through the list of running processes to make sure it is present. —Chad Robinson, chadr@brt.com

There is another possible reason: the connections are being denied by tcpwrappers. Check /etc/hosts.allow, /etc/hosts.deny and /var/log/syslog. —Marc Merlin, merlin@varesearch.com

PPP Locked by Process

I'm trying to connect to my service provider. I got them to tell me how to set it up according to all their specifications through linuxconf, and according to them, the setup is right. When I run ifup ppp0, I get the following message:

pppd 2.3.7 started by root uid0 device is locked by pid438 exit.

How do I unlock ttyS1? —Kirk, webmaster@dcas.net

Looks like there is or was another previous process (438) running, which has or had the /dev/ttyS1 device locked. I think this is the port where your modem is connected. Log in as root, check if the 438 process is still running with ps aux|grep 438; if so, kill or terminate it with kill -HUP 438 and check on the /var/lock directory for any file with a name like “LCK..ttyS1” which is the actual lock file. Remove it and try again. —Felipe E. Barousse, fbarousse@piensa.com

There is also the possibility that two programs are trying to lock the device when you try to dial out. If that appears to be happening (which is most likely the case if there is no lock file but pppd always dies), try removing any lines that say “lock” in /etc/ppp/options. —Steven Pritchard, steve@silug.org

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