Xi6.org

Author Archive

Move ubuntu buttons to right instead of left

by on Jan.27, 2011, under linux/ubuntu

To move the minimize, maximize and close buttons in ubuntu 10.x from the left to right, just use the following command. (You can change the order if you prefer):

gconftool-2 –set /apps/metacity/general/button_layout –type string menu:minimize,maximize,close

Leave a Comment :, more...

Openfiler – Rsync over SSH setup & How-to

by on Jan.12, 2011, under linux/ubuntu

Introduction

Openfiler is a nice little NAS box, but when it comes to setup and configuration you’re pretty much left on your own. There’s no good documentation (even the paid user manual is garbage – it only describes the various checkboxes and fields). The openfiler forums are littered with people asking the same questions you are… and getting no answers.

After hours of searching and messing around, I have rsync over ssh working on openfiler! (Yes, SSH is a requirement in order to secure the data transfer – we don’t want anyone sniffing the traffic and picking up… well, anything).

rsync over SSH on openfiler

LDAP Users & Groups

I’m going to go ahead and make the assumption you’ve successfully setup LDAP and have created a few users and groups. If not, I may write another article pertaining to LDAP as I know it may not be the easiest thing to understand and setup.

On my openfiler system I’ve setup various groups and users as follows:

example: (user-name.group-name)
user.local
backup.remote
external.untrusted

For this article we’ll be focusing in the user “backup” as part of the “remote” usergroup.

File Shares & Permissions

I’ve setup a share called “BACKUPS” which is located at /mnt/volume-group/volume/BACKUPS

I’ve set the remote group as the primary group (PG) and has read/write (RW) access. And have granted the local user read only  (RO) access, so that I’m able to access the share on my local network. (I don’t want to accidentally write things that could possibly screw up rsync at a later date).

Under the host access configuration (Which again I’m assuming you’ve setup “trusted” networks or the ip’s of your external servers/machines that you wish to have connect to your openfiler box). I’ve set my “Remote-servers” network to have Read/Write access to rsync. (Ignore the rsync options for now unless you have specific needs or issues later)

rsync daemon

You may have trouble enabling the rsync service/daemon from the web gui, no problem – login to the openfiler server and start it manually.

#/etc/init.d/rsync start

You may or may not get any errors, should be fairly easy to read the error output and fix as necessary. Below is what my /etc/rsyncd.conf file looks like:

port = 873

motd file = /opt/openfiler/etc/rsync.motd

[ volume-group.volume.BACKUPS ]
path = /mnt/volume-group/volume/BACKUPS
comment = rsync-comment
hosts allow =  192.168.1.1/27 192.168.2.1/29
hosts readonly allow =
auth use pam = yes
read only = no
write only = no
use chroot = no
max connections = 0
list = yes

modifying LDAP user for SSH

In order to properly use our LDAP user “backup” over SSH, we’ll first need to give him a proper home directory (as it’s currently set to /dev/null).

Searching for the user gives us some information:

ldapsearch -x uid=backup

Now in order to modify this user we’ll need to make an ldif file using your fav editor (Keep in mind you’ll need to use the options you’ve set on your openfiler LDAP – hint – accounts tab on openfiler shows the DN info):

#nano backup.ldif

dn: uid=backup,ou=People,dc=openfiler,dc=nas
changetype: modify
replace: homeDirectory
homeDirectory: /tmp

replace: loginShell
loginShell: /bin/bash

Enable SSH for LDAP user “backup”:

[[email protected] ~]# ldapmodify -W -x -D ‘cn=Manager,dc=openfiler,dc=nas’ < ./backup.ldif
Enter LDAP Password: ************
modifying entry “uid=backup,ou=People,dc=openfiler,dc=nas”

Router/Firewall setup – Port forwarding

On my router (wrt54g with tomato firmware), I’ve created a rule that matches the remote client ip (source) and forwards port 22 and 873 to my openfiler box (which iptables also allow those ports).

Remote Client Configuration (files sent from here)

Now onto the good stuff – we’re done with our setup, time to transfer some files from a remote machine to the rsync server.
rsync -avz -e ssh /home [email protected]:/mnt/volume-group/volume/BACKUPS/myserver1
This will prompt you for a password for the user backup. This is fine. We can add SSH keys to remove this prompt and add the command to cron. (I’ll cover this in a later article).
In the above command we’re telling rsync to use -a (archive mode) -v (increase verbosity) -z (compress file data) -e ssh (use the ssh protocol).
There is a difference in using trailing slashes at the end of the directory. I’m backing up my entire /home directory to a directory called /myserver1 (without the trailing slash it creates the directory /home under /myserver1) So we get /myserver1/home. If you add a trailing slash to /myserver1/, the contents of home are written directly into /myserver1/*.

Possible Errors

I’ve written this article after the fact – so I don’t have the countless errors I’ve encountered. Most of the time there’s no associated log output to help you figure out what’s going on. You’ll need to sorta understand how things work in order to better trouble shoot.
You can try running the rsync command without SSH on a few individual test files to make sure that rsync in itself is actually working properly. Then troubleshoot why it won’t work over SSH. (That’s why we modified the LDAP to give the remote user “backup” the ability to have a home directory on SSH) Otherwise we get errors about /dev/null not being a directory.
1 Comment :, , , , more...

Android Task Killers are Useless

by on Mar.29, 2010, under Nexus One

Android Task Killers are Useless

You’ve likely heard of or installed so called “task killers” on your android device to “free up memory” and keep your device running fast. Well sorry to burst the bubble, but they are 100% useless!

They play on the age old misconception that the more “available” memory you have, the faster your computer will be. While this is only “true” (if all memory is used) when you’re running multiple apps at the same time that require the same memory space… which the android stack handles just fine on its own.

We must first understand how android handles applications and states before we have a better understanding of why these task killers are snake oil.

Speaking of snake oil, Android Virus Scanners are Useless – linux doesn’t have “viruses”, and on top of that, each application you run, is contained in its own virtual environment.

When you launch an android app, and then another app, the states are saved for when you return, this doesn’t mean the app is necissarily “running” in the background – it just has its last state stored in memory. Once you open up enough apps, the system will remove states which are no longer necissary – and re-enable them when they are.

The best I can find is to watch this video: (youtube link)

Some task killers actually hinder some default apps. For example, advanced task killer gets in the way of default services connecting and polling refresh updates (ie. Facebook and email) are unable to properly get updates until ATK is uninstalled.

1 Comment : more...

Google Nexus One is an iphone killer!

by on Mar.24, 2010, under Nexus One

Having used an iphone for over 2 years, I can tell you this – the nexus one blows it out of the water! While yes,  the nexus one takes a little getting use to; I initially missed my iphone – only for the single reason that it was so familiar. And the keyboard is a little different, where sometimes I’m hitting the wrong keys, or the voice button accidentally… but I had the same problems when I tried a blackberry. It’s all in what you’re use to typing on previously.

I won’t talk about how the hardware specs are better on the nexus than the iphone, since everyone should know that already.

I also had a jailbroken iphone to make it somewhat useful… the unmodified iphone really isn’t all that much to write home about. So take the “openness” of a jailbroken iphone, and then enhance that to get the nexus one :)

Sales Figures

Don’t get hung up on sales figures or number of apps in the store. The sales figures are based on ZERO marketing. The nexus one wasn’t hyped, wasn’t advertised, just word of mouth among geeks. Just look at the motorola droid, it was marketed and advertised… outsold the iphone in the first 74 days of sales. Just a classic case of apples to oranges. The sales numbers of the nexus one should carry no weight in any comparison in my opinion.

Apps

As far as apps go, while the numbers aren’t in the millions, who cares?! The features and functionality of the apps are by far the most appealing. And out of the current ~30,000 android apps you’ll be sure to find almost everything you need. Did you install a million apps on your iphone? No. No you didn’t.

Some apps that worked on the iphone work substantially better on the nexus one! Take for instance the barcode scanner app (shop savvy, barcode scanner).

I was able to easily scan QR codes, barcodes etc, from a computer monitor even from 4 feet away in a matter of 1-2 seconds. While the iphone struggled in the 1 foot and closer range. I was able to unlock the nexus, open the barcode scanner app; scan the barcode off of the iphones screen! Much faster then the iphone could scan the original code to begin with.

Some have wondered if a regular (laser) barcode scanner can read directly off the screen, and in my experience this is a big fat NO.

I’ve tried it a few times with my iphone during concerts (You know, when you get a ticket with a barcode and they want you to print it off).. Well I printed it just in case, but tried to get the person to scan the barcode off of my screen. (He actually tried a few times) But it’s just too reflective – and not quite how it works.

You’re able to scan barcodes off the screen of another phone because it’s using an imaging device (camera) instead of lasers.

I had about 10 “official” iphone apps, 3 of which were paid versions which I found absolutely necessary in my daily/semi-daily life. The rest I installed, and deleted within 10 minutes of trying them out. Just because there is a ton of apps on the apple store doesn’t make them worth the bandwidth to download.

Also I had jailbroken my iphone to improve its functionality with SMS, settings, and various other user enhancements that are default with the nexus one, or have apps you can easily install without any worries.

Syncing & Integration

The integration/syncing ability of the nexus is fantastic.. wow is all I can say. It syncs with your google account, calendar, contacts, etc… even backs up your phone settings to google! No need to run any crappy (*cough* itunes) 3rd party software on your computer! horray!

And the micro usb connection is wonderful! No need to buy proprietary adapters (Heck, if you’re coming from a blackberry, your car charger should work just fine). It makes it cheap and easy to have a cable at home and the office.

Also transferring music, pictures, files… you just plug it in and it shows up as an external hard drive! Drag and drop your music files, done!

Battery Life

Well since I’ve only had the phone a couple of days, the battery life currently isn’t conducive to my regular day to day activities. (ie. I’m using this thing non stop, and haven’t tweaked it to my liking). So that being said – I’m easily getting 24hours of juice. (On day 3, I’ve only used 55% battery in about 20 hours – I was playing music and using the occasional app to show off the device).

Where as my iphone was very similar when I first got it – but as of late, the iphone got about 8-10 hours or less (and all it did was check 2 email accounts once per hour). I had to have it plugged in if I wanted to listen to music or do anything.

Sadly the iphone has to be sent back for a costly battery upgrade, no thanks! Where as the Nexus one can have its battery replaced in a matter of seconds. Leaving the option there to have a backup battery for when the main runs low. (That in itself is a decision point for many).

Widgets

Another cool thing about the android os, are the widgets! You can place RSS feeds, weather, facebook, calendar, to-do lists, etc… right on your home screen for quick and easy access! And I should mention the home screen(s) are customizable in a similar manner to a pc desktop. Once you place an icon (or folder) on one of the five available home screens, they stay in the location you put them. So customize your most used apps or links to whichever home screen you want.

All of your installed apps are easily accessible from the “rolodex” (I think I’m the first person to use this term to describe it). All the apps are listed in a grid style, alphabetically sorted. Scrolling is smooth and easy.

A side note about scrolling:

While the iphone has the cool “bounce” feature when you reach the top or bottom, the features the nexus/android has in terms of scrolling far outweigh it!

For example: scrolling a long email on the iphone gives me a checkerboard background until I stop and let it load. On the nexus, its showing me the text as I scroll – even at a very fast speed. (So I can see where I need to stop to read what I want). The nexus also shows the scroll bar position at all times! The iphone only shows it while you’re scrolling.

In the android market (ie app store), there’s no “show me next 25″ to a maximum of 50… its you scroll down, more are automatically loaded… indefinitely. And the loading of more apps is so fast and smooth, It was hard for me to notice they were even being loaded.

Conclusion

While there are many many more cool things about the nexus compared to the iphone, I’m going to leave it at that. I did love my iphone for quite some time, I truly did. But there are many big and little things about the nexus one that just destroy the iphone! The LED trackball notifications, expandable memory up to 32 gig! (which can also be encrypted), removable battery, applications able to run in the background, awesome google and gps integration, google voice (which will drop my cell phone bill by $25/month), easy drop in docking that also changes your phone to a visible clock, voice recognition (which works VERY well)… The list goes on…

The only negative I can think of in terms of the nexus relate to an app that isn’t available yet. (Beejive IM). Otherwise it has everything I could ever need and more!

If you’re thinking about buying the device – go for it! I ended up paying around $650 after taxes, freight, etc… I just have to make sure I don’t talk and pee at the same time – accidentally dropping it in the toilet.

1 Comment :, , , more...

Citrix Xenserver Raid (Fakeraid/software raid)

by on Sep.14, 2009, under Virtualization

Xenserver doesn’t “really” support fakeraid or software raid.

Fakeraid is that of an onboard or bios type raid. All the processing is done by your CPU and is similar to software raid in that regard. But software raid is handled by the Kernel or OS.

A hardware RAID card is expensive (~$400 additional cost to a system), and is typically proprietary in the way it writes data. So if it does happen to fail, you may be SOL when replacing with a different card – or quite often the same card with a slight variation in the firmware.

These days I would say software raid is comparable in performance to hardware, but can more easily be patched or moved across different systems.

While I would like to use software raid on my xenserver installation (And it is “possible”), it’s just a little bit too much patching/hacking to get working… And there is a bit of uncertainty to what happens when the host is updated to a more recent xenserver version.

Now fakeraid is “semi-supported” on a xenserver installation… meaning you can fake raid a storage repository, but not the entire host. You’ll be better off with some raid than no raid.

You’ll need a minimum of three (3) hard drives for a fakeraid on xenserver. (one will be used to install the host, and the others will be raided for VM storage). So we’re limited to a point of failure of the host hard disk… meaning at worst if that fails you should still be able to access/restore VM’s on another xenserver (or re-install the host on a new HD and still have access to the raided storage when you add it again).

On this installation I’ll be using a 200GB drive for the host. (And may use this drive to store ISO’s and other misc files). And all my virtual machine data will be on the raided drives.

You can setup your bios raid (fakeraid) with 1 drive non-raided (the one that will hold the host), and the other drives in a raid array.

During the xenserver installation you will be asked which drive to install on. All your drives will display (non-raided), so choose the single drive you know isn’t in the array (Mine is SDA). And when asked which will be used as the default storage repository, choose the same single drive or none at all.

Once the host boots up you should get into the console.

Make sure the proper modules are installed:

# insmod /lib/modules/$(uname -r)/kernel/driver/md/dm-mod.ko
# insmod /lib/modules/$(uname -r)/kernel/driver/md/dm-mirror.ko

(This would be for a RAID1 mirror)

Execute the following command in order to init the raid:

# dmraid -ay -v

The raid device should show up as /dev/mapper/RaidVol0 (or whatever you called the raid volume in the bios).

Now we’ll want to create a new SR (storage repository) using the RAID volume:

# sm create /dev/mapper/RaidVol0

In order to have the repo avail on boot in /etc/smtab:

# xe host-sr-set -u root sr-id=rep_uuid active=true

Attach the Storage Repository:

# sm attach <rep_uuid> none

See if its active:

# sm info

If not active, restart smtab and xenagentd:

# service smtab restart
# service xenagentd restart

And that should do it.

2 Comments :, , , , , more...

XenServer (citrix) vs ESXi (vmware) vs Xen (opensource)

by on Aug.13, 2009, under Virtualization

A common question in virtualization, which option is better.

We’ll take a look at the top options. (HyperV and KVM aside because quite honestly they suck). Sorry if you’re using either of those as a virtualization solution — but HyperV is bloated and based on windows… and KVM by nature is very insecure. On somewhat of a sidenote, it’s quite unfortunate that there are so many people in the world that get “sold” by gimmicks, bulleted lists and various other hyped up garbage.

Lets start off with a basic comparison on XenServer vs Xen. Both of which are free. Xen is opensource, while XenServer is based upon Xen, it’s owned by Citrix. (It may be useful to point out that XenServer is similar to ESXi, where as Xen is quite a bit different from both).

Xen (opensource) requires a base operating system (Dom0). So for instance you would install Ubuntu or CentOS first, having a fully operating desktop machine. On top of that you would install opensource Xen and a virtual maching manager tool. You are then able to create virtual machines on top of your host OS. (While you don’t necissarly need to install the x-windows system on Dom0, it still requires a base OS as such).

The opensource Xen solution is probably a good solution for your home network. I used open source Xen on my single desktop machine (3TB HD, 4GB ram, Quad Core Processor). Which allowed me to keep my base Ubuntu installation for development, web browsing, and various other things I do on my home desktop. But also allowed me to create a media server for streaming music and videos to my PS3, a VOIP server to manage calls, a ZoneMinder server to monitor IP cameras and create a new test server when I needed to play around with other applications in a server environment.

Now looking at XenServer (citrix) and ESXi (VMware), both of which are “free” and have extra licenses you can purchase for several thousand (to several hundred thousand) dollars in order to open up some pretty cool “enterprise” features. While both can server a production environment quite well in their free versions, having used both, XenServer is a better solution. Both are a barebones/baremetal type hypervisor and take about 10-15 minutes to install. (Unless of course you run across some hardware incompability issues). But that may only be a problem with very old hardware or perhaps very new cutting edge technology.

XenServer itself has more free features out of the box, and is all around a better implemntation. One of the biggest features (though actually small), is that XenServer uses IPtables!! I can easily setup firewall rules on the hypervisor itself, helping keep my server SECURE. Where as with ESXi, the command console is VERY limited. I had to create an additional virtual machine firewall appliance, then connect my management console to the virtual machine and setup port forward rules from the virtual machine to the management interface. (So if the VM crashed, I was pretty much SOL).

Another great feature of XenServer is the ease of clustering up to 16 physical servers together! This allows for High Availability failover and high  workloads to be distributed to other servers in the cluster. It’s as simple as point and click, as well as a simple drag/drop to move one VM to another physical machine. (In HA mode, a failed server automatically migrates the VM’s to another machine). Though I believe HA requires an enterprise license.

ESXi itself doesn’t have much in terms of “cool” features, I found it kind of boring actually. I guess the only thing notable about ESXi is that you can run unmodified guests without too much “performance loss”. (Though I did find ESXi painfully slow compared to XenServer with the same Virtual Machines running).

Another thing I found is that with ESXi, creating VM’s was pretty easy; but duplicating a VM was time consuming. I/O operations are very sluggish on the system itself. XenServer allows you to template a VM so they can be duplicated quickly and easily once you had created the initial install of one VM. XenServer saves hours of time when it comes to this feature.

I guess it’s becoming pretty aparent that XenServer (citrix) is just better. On two identical physical servers (Dual Quad core processors, 16gb of ram), XenServer (besides having better management features) performed much better in comparison to the same VM installations on the ESXi host.

All VM’s were linux (CentOS) based. I don’t run windows for anything aside from the odd desktop machine here and there (if that). Though running windows hosts on ESXi is (i believe at the moment) easier then XenServer.

11 Comments :, , , , more...

Apple Iphone Shuffle not random

by on Jul.20, 2009, under Uncategorized

As the topic says it all… the shuffle or random mode in the iphone (or maybe even the ipods in general) are not random! You’ve noticed the same songs play in the same “random” order.. annoying I know.

I remember creating a random number generator back in school (in the C programming language), but to my surprise the rand function wasn’t actually random! Maybe the first time around it seemed random… but it was the same random every time you ran the program. You had to custom code the random to be truly random.

So I’m guessing there are just some lazy programmers working at apple that can’t write a proper shuffle program.

Though recently I’ve heard people say that it shuffles the entire play list when you start up (power on) or whatever… which may be the case… but that is also a very poor way to do it!

No one turns their phone off very often or at all if its not necessary. I leave my phone on until it starts to bug out and lock up.

I want my shuffle to be random for each song! wow that would be great! A shuffle program the way it’s expected to be? Whaatt? no way!

Most of my older mp3 players (and hell, even my portable CD player and car) have this button called “random”. When I press it, a random song plays. When I click “previous”, a random song plays, when i click “next” a totally new random song plays! It’s a surprise every time! I love it!

But unfortunately with the apple iphone I press back and it plays what I just listened to (ok not horrible)… but when i press next, i feel like i know what song is going to play next… and I do… and its sad.

I only have a modest library of around 1,000 songs on my iphone. But unfortunately every day I listen to the same hundred or so damn songs over and over and over. It’s annoying that I can’t get any variety in my ipod!

I’ve resorted to closing my eyes and picking songs from the song list with a few flicks up or down beforehand. It’s a better random than the iphone provides that’s for sure.

Update – Nexus One:

I’ve recently switched to Googles Nexus One phone and found the shuffle on this device works absolutely fantastic! I have the same songs, yet the listening experience is easily 2-3 times as good!

When listening to music, you can easily turn shuffle on or off from the currently playing song. (No need to go back a menu or two in, scroll up to the top of the list and select “shuffle”). Nexus One’s shuffle is right on the screen that’s displaying the current song; along with the option to repeat current song, or continuously loop your playlist.

Pressing the back button on the track, brings you to the last listened track (and pressing it again brings you to the track you listened before that one). Now at anytime you press “next”, even if you pressed the back button, it provides you with a RANDOM song! Imagine that! The people at google sure got this right.

It’s funny, while I have the same few hundred songs, I’m listening to ones I haven’t heard once on my iphone… wow :)

The nexus one media player also has the ability to drag a slider back and forth and skip to whichever section of the song  you wish! Very cool. The only thing it doesn’t do out of the box is display the currently playing song on the lock screen. (Not a huge deal, and I’m sure there’s a widget for that).

3 Comments :, , , , more...

Software RAID Ubuntu 9.04 Linux

by on Jul.16, 2009, under linux/ubuntu

Setting up software RAID is “fairly” easy. But first you must install the ALTERNATE installation CD for Ubuntu. (CentOS is pretty straight forward when you select “manual partitioning” in the GUI installer on the regular ISO).

Once you download and burn the alternate ubuntu ISO for your cpu architecture, boot it up on the machine you want to install. (Note: this will erase data on the drives, so make sure no external drives are connected, or any drives in the system you don’t want raided).

During the install, when you come to partitioning, select manual and delete the partitioning tables that currently exist on your drives so that each drive has “FREE SPACE” as the only option under the device.

I’m going to be setting up RAID5, which in my opinion is the best balance between performance and redundancy. (This box is going to be a media server / backup / desktop with three TB drives).

Now for my first device (HD) I’m setting up 3 partitions, (boot, root, and swap). I create the first primary partition of 100MB at the beginning of the drive and set the “use for RAID” where you might normally select ext3, boot, swap etc.  Also be sure to add the boot flag to this partition.

The second partition I setup as logical 6GB and “use for RAID” selected here as well. And the third I set the remainder as a primary partition and “use for RAID”.

I repeat these partitions on the remainder of the 2 drives so each of the 3 drives have identical partition tables.

Next we’re going to select “configure software RAID” that is at the top of the menu, and create a new MD (Multi Disk) device.

Keep in mind we have 3 partitions per disk, totalling 9. So we will have to create 3 MD devices in order to raid each partition.

Creating the first MD device we select RAID1 (mirroring) for the boot partition. This will allow the system to boot properly. (This single raid 1 is very important to our system functioning).

For number of active devices, we type in 3. And 0 spares. Selecting /dev/sda1, /dev/sdb1, and /dev/sdc1 in the device list.

We will repeat creating an MD for each “set” of partitions. (for a total of 3 times). But these subsequent partitions will be RAID5.

You will be presented with RAID MD devices showing up on the partition overview. This is when we will set these partitions to EXT3, SWAP etc…

The 100MB raid1 partition we will set up as EXT3 mounted at /boot. This raid1 will allow the system to boot and not throw a grub error 2 at us.

The 12GB raid partition will be set up as SWAP

And the 2TB partition will be set up as EXT3 mounted at root /

Once we have those set, we finish and write to partition table. It’ll format the drives, sync the arrays and install the OS.

After that’s all said and done it’ll want to reboot. And we’re finished!

5 Comments :, , , more...

GRUB Error 2 Ubuntu 9.04 RAID

by on Jul.16, 2009, under linux/ubuntu

After installing software RAID, or perhaps for some other reason – you’re presented with a system that cannot boot properly. In my case, I installed a RAID5 Array and was presented with a GRUB ERROR:2 on boot.

GRUB Error 2 is basically “Selected Disk does not exist“.

Which likely means that grub is pointing to a disk or device that is either not recognized or as stated, doesn’t exist. It may be pointing to (hd0 0,1)  instead of (hd0 0,0) or whichever missconfig. In my case with the newly installed RAID, it’s likely the issue of GRUB being non-existant on subsequent disks, or not mapped properly to the MD array.

To fix this error after a RAID install, I had to go back in with the alternate installation CD and modify my RAID on the /boot partion (100MB).

Instead of this being a RAID5, I changed it to be RAID1 (mirroring) instead. So instead of 1 drive having the pairity value, the 3 drives now have an exact copy of the static boot files. We’re now able to boot our system!

Otherwise you may have to manually edit GRUB and change the device it’s trying to boot. (Such as mentioned above where it may be trying to boot into hd0 0,1 instead of hd0 0,0)

1 Comment :, , , more...

Migrating Virtual Machine (VM) FROM esx to xen server

by on Jul.09, 2009, under linux/ubuntu

There seems to be a lot of posts and resources on how to migrate the other way around – but WHY?! Why would anyone want to migrate from Xen to ESX? I’ve had so many issues with ESX I’m spending thousands to create another server and migrate TO Xen!

At the time I needed a relatively quick deployment of a server which I could easily manage virtual machines etc. (Well ESXi seemed like the answer). With only about a week to get the hardware, install and send off, I managed to get it working (I can’t say installation was that easy considering the limited hardware support ESX offers).

Needless to say, after deployment I was noticing VERY poor disk performance. (Yes I installed vmware tools and all that garbage). I tweaked, re-tweaked, re-installed virtual machines, resource pools, etc etc… weeks and months go by trying to fix the piss poor performance. No one on the community forums could help – It seems everyone is running windows guests and suggesting a bunch of stuff that would never make a difference anyways. If i’m getting crappy performance with freshly installed Linux guests, something is wrong with the hypervisor (ESXi).

In any case, I can’t take it anymore – ESX has to go! Reluctant to spend another $3,000 in order to mirror the server (extended downtime to rebuild is not an option). Plus the fact that on ESX I had to install a VM specific to being the firewall for the machine. Why ESX doesn’t have iptables or any firewall/routing built in is beyond me. It’s very insecure without adding additional overhead with another virtual machine appliance.

So while I build a new server and install Xen, It’s so much better! WOOWWW! Not only does it have better features, the performance is about 4x better! I love being able to “template” a VM of a base install, then deploying it quickly and easily as a new machine. The performance is near native (I can’t tell the difference opposed to if it was a single server installed on bare hardware). Where as with ESX, I could notice the sluggishness.

Now onto the main point of this article: Converting a VM from esx to Xen!

This portion coming soon – please leave a comment if you’d like it sooner than later.

1 Comment :, , , , , , , , more...

Looking for something?

Use the form below to search the site:

Still not finding what you're looking for? Drop a comment on a post or contact us so we can take care of it!

Visit our friends!

A few highly recommended friends...