What To Do: Users Still Wants Telnet

Posted on in Categories CentOS, fedora linux, GNU/Open source, High performance computing, Howto, Linux, package management, RedHat/Fedora Linux, Security, Ubuntu Linux, UNIX last updated August 26, 2008

TELNET (TELecommunication NETwork) is a network protocol used on the Internet or local area network (LAN) connections. It was developed in late 60s with RFC 15. Telnet is pretty old for login into remote system and it has serious security problem. Most admins will recommend using Open SSH (secure shell) for all remote activities. But you may find users who are still demanding telnet over ssh as they are comfortable with Telnet. Some users got scripts written in 90s and they don’t want to change it. So what do you do when users demands telnet?

CentOS / Red Hat Enterprise Linux 5.2 Poor NFS Performance and Solution

Posted on in Categories Apache, CentOS, data center, File system, High performance computing, Howto, Linux, Linux distribution, Networking, package management, RedHat/Fedora Linux, Security Alert, Storage, Sys admin, Troubleshooting, Tuning last updated August 22, 2008

A few days ago I noticed that NFS performance between a web server node and NFS server went down by 50%. NFS was optimized and the only thing was updated Red Hat kernel v5.2. I also noticed same trend on CentOS 5.2 64 bit edition.