Skip to content

Author: DB Cooper

Vmware – Linux Host / Linux Guest – Keyboard Mappings Issues

Quick Tips from the field.

If you’re running a Linux host with a Linux guest and are having issues with your keyboard keys being mapped wrong inside your VM. (Like my up arrow was remapped to “Print” etc)

Then you can try the following.
edit the following file: /etc/vmware/config

Add the following:
xkeymap.nokeycodeMap = true

save the file.

Make sure vmware isn’t running and restart the vmware services like….

#sudo /etc/init.d/vmware restart

Then launch vmware again.

HTH

RHEL – Xen vs. KVM

Let me just say I’m a big VMware fan. And since they started giving out ESXi for free, I try to pass on the love as much as possible.

However, sticking to open source values is very important to me for many reasons, and I recently discovered Xen is going away in RedHat Enterprise Linux (RHEL). I kinda figured it would die out as soon as Citrix bought up Xen.

So I dug around after a few emails with another virt guy.

Red Hat’s official statement:

http://www.redhat.com/about/news/prarchive/2008/virtualization.html

I guess if you’re sticking with RHEL’s way of doing things, you had better give up on Xen and start working with KVM / Ovirt etc.

It seems Xen will continue to be supported through the 5.x series, as they have lots of customers using it. (hmmm…)

So I guess there will be a tool or some article for transitioning later on.

Ovirt – http://ovirt.org/
KVM – http://kvm.qumranet.com/kvmwiki/Front_Page
FreeIPA – http://www.freeipa.org

However, this is all in a beta area for now.

My thoughts would be to simply go with VMware Server or ESXi server for production and then start testing the KVM solutions for future configurations. That’s just my two cents.

HTH

OpenJDK6 – Java 1.6.x on CentOS 5.x

Just a quick tip that might help out the folks needing something better than gcj and still using an open version of Java.

On CentOS 5.2 :

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-2.noarch.rpm
yum install -y java-1.6.0-openjdk-plugin java-1.6.0-openjdk-devel java-1.6.0-openjdk

😉

Hope that makes someone’s life easier!

Who’s hogging the pipe?

If you’ve found yourself in a Network/System Admin position without the proper tools, and can’t seem to get them, there’s usually a way to do things for free with Linux or at least using the repos provided under an enterprise support package such as RHEL. 🙂 This is for monitoring who’s chewing up the pipe by IP address.

* Obviously there’s 100 ways to skin a cat in Open Source, but this is one way that can take you from “Who’s hogging the pipe” to “HEY! Stop doing that” in 15 minutes. Granted this isn’t meant for controlling the traffic, that’s another story. *

How To: ( Warning! – You may need to verify this action with your IT Dept – Warning!)

1. On the Core switch just before the “Gateway” hop takes place, and Pre-NAT rules, you’ll need to enable a port for monitoring the traffic (both TX and RX) to and from the “Gateway”. This box could also be used as a SNORT box. (once again another story)

2. You’ll need a Linux box with dual NIC’s (for remote usage) or a single NIC with Physical terminal access for direct access only.

3. Install and run/configure “iptraf” (using sudo or root access) 
#sudo yum install -y iptraf
#sudo iptraf (once the Screen launches, hit any key)
Scroll down to “Configure” (enter)
Set “Force Promiscuous mode” to ON
(You may wish to keep “Reverse DNS Lookups” off as well)
(Adjust “Additional ports” or any other settings if needed)
“Exit Configuration”
Select “IP Traffic Monitor”
Select the interface that’s plugged into the “Monitored” port. (from Step 1.)
Once the monitoring begins you can sort by bytes or packet count etc.

Find the “Hogger”.

Note: I really like the “iftop” tool as well, but it’s not in the RHEL Repos. ;0)

You can’t control the traffic from this app, but at least you can verify if the traffic is legit or not. Once you have the ip you can do the standard ip/arp/mac table lookups etc. to locate the machine.

HTH.

dbcooper