Best of Technical Support
I'm running a small private LAN with Linux Red Hat 7.0. The following command was entered on system “lucy”, with the resultant message:
[root@lucy]# tar cvf testbed:/home/someuser file.txt Permission denied. tar: testbed\:/home/someuser: Cannot open: Input/output error tar: Error is not recoverable: exiting now
This output is from the /var/log/messages file on the system “testbed”:
Mar 30 08:14:57 testbed pam_rhosts_auth[853]: denied to root@lucy as root: access not allowed Mar 30 08:14:57 testbed in.rshd[853]: rsh denied to root@lucy as root: Permission denied. Mar 30 08:14:57 testbed in.rshd[853]: rsh command was '/etc/rmt'I have been reading about PAM but have not figured it out yet. Could someone give me assistance to make this command work? I don't mind if I temporally dummy up my security in /etc/pam.d, but my last attempt made it impossible to even log in. Ouch! —Les Hilliard, les.hilliard@home.com
On the machine where you want to put the tar file, create a .rhosts file in the home directory, with 0400 permissions. The .rhosts file should a single line, “X.X.X.X user”, where X.X.X.X is the IP address of the machine where the tar command is run and the user is the user id of the person running the command. Run the following command on the other machine:
tar -cvf root@mm:/root/aaa.tar work/
where mm is the remote machine name or IP address and work is the local directory. Beware that this will also allow rlogin without a prompt for password. —Usman S. Ansari, uansari@yahoo.com
I recently installed Netscape 4.7.6 on my Linux machine (the machine was recently rebuilt, so the kernel and libraries are very recent). When I was trying to run it, I got the following error message:
/usr/local/bin/netscape /usr/local/bin/netscape: error in loading shared libraries: libstdc++-libc6.1-1.so.2: cannot open shared object file: No such file or directory
Checking my libraries confirmed that I didn't have that particular library installed, but a newer one:
# cd /usr/lib # ls libstdc++* libstdc++-3-libc6.1-2-2.10.0.a libstdc++.a.2.10.0 libstdc++-3-libc6.1-2-2.10.0.so libstdc++-libc6.1.so libstdc++-libc6.1-2.a.3 libstdc++-libc6.1-2.so.3I successfully resolved the problem by providing a symbolic link to the newer library:
# ln -s libstdc++-libc6.1-2.so.3 libstdc++-libc6.1-1.so.2This solved the problem, and Netscape is running smoothly. However, this incident left me with a number of questions:
What is the meaning of the .2 and .3 at the end of the filename?
Is this solution appropriate? I would have liked to create a shorter link, like libstdc++-libc6.1.so, but that didn't work. Would it have been more appropriate to actually find libc6.1-1 and install it next to the existing one?
My assumption is the Netscape binaries had the library version hardcoded (I believe this version of Netscape is not available as source code); is that correct? —Michael, micky@alum.mit.edu
The reason a library maintainer changes a revision is there is a significant change in the underlying code or interface. The maintainer usually feels it would not be wise for a program dynamically linked with an older version of the library to automatically work with the newer version. “Appropriate” is in the eyes of the beholder. It is possible that the dynamically linked program you are “tricking” could disastrously crash, destroying itself and other things. Most likely, though, it won't. But, it definitely would be safer to find the actual dynamically linked library. The Netscape 4.x binaries have some interfaces (to the dynamically linked library) and versions hard coded. —Christopher Wingert, cwingert@qualcomm.com
I am currently using Mandrake 7.2 as a server platform. I do not want to run X. I have tried all configuration options on the Mandrake install, and even manually deselected X components, but the install just goes ahead and installs X anyway. Is there a way of stopping X and X components from being installed?
Also, when in console mode, is there a way to stop the monitor from going into power save mode? I have disabled the apm dæmon and power management in the BIOS, but the monitor keeps shutting down. —Gerard Nicol, gerard.nicol@tapems.com.au
Use rpm -qa to uninstall packages you may not need. You should also keep a list of the packages you uninstall so you can install them again, if needed. To disable power saving in the console, do setterm -blank 0. —Usman S. Ansari, uansari@yahoo.com
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Sponsored by AMD
If you already use virtualized infrastructure, you are well on your way to leveraging the power of the cloud. Virtualization offers the promise of limitless resources, but how do you manage that scalability when your DevOps team doesn’t scale? In today’s hypercompetitive markets, fast results can make a difference between leading the pack vs. obsolescence. Organizations need more benefits from cloud computing than just raw resources. They need agility, flexibility, convenience, ROI, and control.
Stackato private Platform-as-a-Service technology from ActiveState extends your private cloud infrastructure by creating a private PaaS to provide on-demand availability, flexibility, control, and ultimately, faster time-to-market for your enterprise.
Sponsored by ActiveState
| Non-Linux FOSS: libnotify, OS X Style | Jun 18, 2013 |
| Containers—Not Virtual Machines—Are the Future Cloud | Jun 17, 2013 |
| Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer | Jun 12, 2013 |
| Weechat, Irssi's Little Brother | Jun 11, 2013 |
| One Tail Just Isn't Enough | Jun 07, 2013 |
| Introduction to MapReduce with Hadoop on Linux | Jun 05, 2013 |
- Containers—Not Virtual Machines—Are the Future Cloud
- Non-Linux FOSS: libnotify, OS X Style
- Linux Systems Administrator
- Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer
- Validate an E-Mail Address with PHP, the Right Way
- Senior Perl Developer
- Technical Support Rep
- UX Designer
- Introduction to MapReduce with Hadoop on Linux
- Web & UI Developer (JavaScript & j Query)
Featured Jobs
| Linux Systems Administrator | Houston and Austin, Texas | Host Gator |
| Senior Perl Developer | Austin, Texas | Host Gator |
| Technical Support Rep | Houston and Austin, Texas | Host Gator |
| UX Designer | Austin, Texas | Host Gator |
| Web & UI Developer (JavaScript & j Query) | Austin, Texas | Host Gator |
Free Webinar: Hadoop
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Some of key questions to be discussed are:
- What is the “typical” Hadoop cluster and what should be installed on the different machine types?
- Why should you consider the typical workload patterns when making your hardware decisions?
- Are all microservers created equal for Hadoop deployments?
- How do I plan for expansion if I require more compute, memory, storage or networking?




2 hours 32 min ago
2 hours 58 min ago
5 hours 26 min ago
5 hours 59 min ago
6 hours 47 sec ago
6 hours 1 min ago
6 hours 3 min ago
6 hours 4 min ago
6 hours 6 min ago
6 hours 7 min ago