Best of Technical Support

Our experts answer your technical questions.
Setting Up for Games

I am trying to set up my firewall so that my users can play on-line games. In particular, I need to set up the following ports:

  • An initial outbound TCP connection on port 47624

  • Subsequent connections of inbound and outbound TCP and UDP ports 2300-2400

I am using IP masquerading. My firewall is an ipforwarding one, i.e., not a proxy firewall. Any help you can give me would be greatly appreciated. —Neil Shanks, neilshanks@home.com

Unless you set up additional firewalling rules, there is no way to allow the outbound packet on port 47624. Outbound UDP and TCP connections in the 2300-2400 range will work fine, and the masquerading machine will open a reverse connection to gateway back inbound packets if they come back on the same port. If they don't, you may have some luck with the ipautofw packet forwarder which you can get at ftp://ftp.funet.fi/pub/Linux/PEOPLE/Linus/net-source/firewall/ipautofw.tar.gz. You may also want to look at the ipmasq-HOWTO and the list of applications that can be made to work through IP masquerading, http://users.nais.com/~nevo/masq/. —Marc Merlin, marc@merlins.org

Downloading with Netscape

Is there a default directory for downloads? I used the included Netscape Communicator v4.07 to download the Corel WordPerfect Suite 8 for Linux (a 25MB download that took a couple hours) and the Quake 2 for Linux demo. When I went looking for the files to install them, I couldn't find them anywhere. The system did not ask for a specific location to place them, so I assumed there was a default location. Am I wrong? —Robert Gray, noeman5@hotmail.com

By default, Netscape tries to save the file in the user's home directory or the last place (path) where you saved a file. To locate the files, use the command find:

find / -name "corel*.tgz" -print

—Mario Bittencourt, mneto@buriti.com

More on Recovering Data

I had a hard disk crash and cannot mount root directory /dev/hda3. Is there any way to perform a partial recovery of the data on the drive or split the root partition (skipping the bad sectors) from a boot floppy? I only need the most recent data in the mail directory that was not backed up. —Tom Voydanoff, tvoydan@systechcorp.com

Boot using a rescue disk and try to repair the partition with the command fsck.ext2 /dev/hda3. After that completes, try to mount the partition yourself and dig out the needed files. —Mario Bittencourt, mneto@buriti.com

Errors in Hard Drive

I have a Linux system that the hard drive died on. I have a tape backup of the entire system. I did a minimum install of Red Hat to get the new drive running, created the partitions / and /big and told taper to overwrite all files. It ran and restored its files but had over 1200 errors. I viewed the log, which contained statements about checksums not really errors. I was hoping to be all right, but when I rebooted, the system just printed LI and stopped. Any help you could offer would be greatly welcomed. —Jabe Pitts, Jabe.Pitts@cwix.com

Your system is probably fine—this is a boot loader issue. Boot loaders need to know where the kernel is located, and by restoring your tape, you overwrote the kernel, which moved it to a new position on the drive. Use a boot floppy to boot your system and run lilo. This will reinstall the boot loader. (Note that you may need to use —Chad Robinson, chad.robinson@brt.com

Installing guile

I got a message like the one below when I was trying to install guile. I usually can figure out what needs to be installed when I get these failed dependency messages, but this time I'm flummoxed. I have both glibc 2.0.7 and 2.1.x installed. Is this just a peculiarity of the RPM? I've gotten this message with a bunch of RPMs I've tried to install recently, not just this one.

[root@localhost new]# rpm -Uvh guile-1.3-4.i386.rpm
failed dependencies:
libdl.so.2(GLIBC_2.1) is needed by guile-1.3-4
libdl.so.2(GLIBC_2.0) is needed by guile-1.3-4
libm.so.6(GLIBC_2.1) is needed by guile-1.3-4
...

—Brady Hegberg, bradyh@bitstream.net

Well, it turns out that glibc 2.1 isn't exactly binary compatible with glibc 2.0. It looks like that's the problem you're having. Grab the .src.rpm file instead, and do

rpm --rebuild guile-1.3-4.src.rpm.

The resulting .i386.rpm should work and will be in the /usr/src/redhat/RPMS/i386/ directory. —Marc Merlin, marc@merlins.org

______________________

Webinar
One Click, Universal Protection: Implementing Centralized Security Policies on Linux Systems

As Linux continues to play an ever increasing role in corporate data centers and institutions, ensuring the integrity and protection of these systems must be a priority. With 60% of the world's websites and an increasing share of organization's mission-critical workloads running on Linux, failing to stop malware and other advanced threats on Linux can increasingly impact an organization's reputation and bottom line.

Learn More

Sponsored by Bit9

Webinar
Linux Backup and Recovery Webinar

Most companies incorporate backup procedures for critical data, which can be restored quickly if a loss occurs. However, fewer companies are prepared for catastrophic system failures, in which they lose all data, the entire operating system, applications, settings, patches and more, reducing their system(s) to “bare metal.” After all, before data can be restored to a system, there must be a system to restore it to.

In this one hour webinar, learn how to enhance your existing backup strategies for better disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible bare-metal recovery solution for UNIX and Linux systems.

Learn More

Sponsored by Storix