Posted by bitbud on November 19, 2008 under How To, Rock Solid IT, SAN, Virtualization | 
Picking a Path
Note: There are other options for getting a SAN for your use. For example, there are iSCSI Target applications that you can add to Windows to allow it to function as an iSCSI server. My focus here is on serious, production use of SAN technology. It has to be rock solid stable and running for years with minimal maintenance. Moving on…
When you think of your SAN (or any IT system, for that matter) there are two areas to address: the hardware and the software. There are many ways to go about putting together a SAN for your environment. Some possible options might be:
- Buy a SAN from a SAN provider: Equalogic/ Dell, Compellent, or Xiotech.
This is your hardware and software in one package. This will provide you with a quick, high quality solution with an easy to use interface. You won’t even need an in-depth understanding of the technologies involved, as it is all nicely packaged for you. The biggest barrier is usually the cost. If that’s not an issue for you, if you are comfortable with someone else being responsible for your critical software stack, and you’d rather not get into the nitty-gritty of SANs (i.e., you want the super easy way to do it :-)), then I can point you to an honest brother who is a reseller.
- Buy a commercial application for PC/ Server hardware to turn it into a SAN.
A good example would be the application San Melody, which I have been told works quite well. Of course, you need the appropriate hardware, and the license is a little expensive. Like option 1, it is nicely packaged and you don’t have to get your hands dirty with the technical details.
- Use a completely free and open source system like OpenFiler.
This system, like San Melody, will provide you will a packaged software solution that you install on your own hardware. It has many easy to use features. It probably requires just a little bit more technical understanding than options 1 and 2, but it is still easy to use and best of all, its free.
- Use Linux <— (placed on a line all by itself for dramatic effect)
… or more specifically, use Linux with a few specific packages: LVM2, iSCSI Enterprise Target, Ethernet Bonding, and (if you want to cluster, like I do) NFS. This is what I will focus on the rest of this series of SAN articles And yes, this is what OpenFiler offers in a completely packaged system. I’ll go into detail soon why I am not using it later.
Don’t assume that must give up some feature or functionality by using Linux. On the contrary, for a much reduced cost you can have the equivalent system (I would argue a better system). For me, Linux has become my Swiss Army Knife of SANs. The same stable system can be used on low-end or high-end hardware, which keeps administrative costs down (keep it simple). On the low-end: in Part 1 I mentioned that I built a full featured system (minus stellar performance and some hardware redundancy) for less than $500 with spare PCs and a few new hard drives. On the high-end: if you do have some money to spend on hardware, and need the best in performance and redundancy, you can purchase the same redundant hardware as a commercial SAN, same hardware warranty, for only 10%-25% of the cost!
I didn’t arrive at option 4 lightly, but after several months of investigation, testing, and consideration of these options. There were several aspects to consider:
- Cost. The cost factor can’t be ignored. It wasn’t the biggest reason for me, but it will be for most. It is important to be a good steward your resources, regardless of how limited or unlimited they may be, the money spent has to be considered
- Ease of use. I’m sure some will disagree, but I don’t think having a GUI automatically makes something easier to use. In the case of a critical component like a SAN, a GUI may simply make it easier to break. If you think typing an e-mail is easy, and you can handle typing a few sentences from instructions, then using Linux from the command line for managing a SAN is easy too. In fact, you could argue that typing in a command is much more precise than clicking around a GUI, and therefore could be easier to use, especially considering the importance of getting it right.
- Rock Solid IT. A SAN is about as critical a component as you can have. All your data is congregated in one place. It is the disk space for all your servers. It has to run all the time with no down time - it has to work. Period.
- Good Stewardship. Someone else will eventually need to come behind you and work on this. You WANT others to be able to help. I toyed with this thought for a while, as as a friend from the RT pointed out to me to make sure it was covered. See ‘Ease of Use’ above, I think so long as you document what you have done, and how to do it, you cover the ability for someone else to pick it up. The interface doesn’t really matter.
- Ownership. I’m an engineer. I realize everyone in IT may not be an engineer, but for me there is a huge value add when not using a proprietary software stack. The ability to fully own what you are using, and not be open to a company pulling the rug out from under you when you least expect it (as can happen with proprietary/ closed source offerings). Some see the Linux/ Open Source aspect as a disadvantage, but I disagree. True, you do need some technical knowledge, but you hopefully do, working in IT. For me, I am the last line of support, not some vendor. If I am responsible for a system, I should understand in 100% and be able to address any issues with it. Others would disagree, and prefer to outsource that responsibility, and I understand how they arrive at that conclusion. On that note, I will tell you that this IS easy to do, and if you follow good production IT principles (like testing and stabilizing production systems before implementation) you will have a system that will be Rock Solid reliable.
Here’s whats coming up in the SAN For All series:
- Specs for building a high-end, fully redundant 16 TB SAN for less than $9000
- Implementing a SAN for cheap
- Installing an iSCSI SAN - Step by step process for using Ubuntu LTS Linux as a Rock Solid SAN
- Working with physical disks and LVM2
- Configuring iSCSI Targets
- Managing LVs - snapshots, resizing
- Configuring Network bonding - How to get 10Gb speed with redundancy for less
- Virtualization methodologies
- NFS for clustering, just like an HPC
- RAID configuration suggestions
Posted by bitbud on November 14, 2008 under Bitbud Blog |
Welcome to the new bitbud.com I have finally flipped the switch from Joomla to Wordpress, and I have to admit the new Wordpress 2.7 is sweet. This is by far THE platform to use for a Blog. I tried for several months each both Drupal and Joomla. They are good CMS systems, but for blogging, the new Wordpress can’t be beat. This really is making blogging MUCH easier for me.
I found a useful script that handled the importing of all my Joomla ‘articles’. Sadly, none of the comments made it, but I may do that manually later.
There is still more work to do, most importantly handling redirects from the old Joomla links to the new Wordpress permalinks. Also need to import my graphics, find a new template, and get my modules configured.
I’ll update this post with some more details on the script I used for importing later.
Enjoy!
Posted by on November 12, 2008 under Uncategorized |
I have been withholding my posts lately, as I am working on moving over to WordPress (should be done this week). However, this news is too big to wait.
The new version of KVM (KVM-79) was just released, and it includes a feature that is unique to KVM (compared to all other x86 virtualization platforms - in other words, VMWare and Microsoft can’t do this, but I’m sure they’ll add it soon),
PCI device assignment
With this new release, you can now pass an entire PCI device directly to a Guest virtual machine. No emulation or para-virtualization required. If you understand what that means, then you understand just how cool it is. This is HUGE, both in the virtualization world, and for PCs in general. In time, the paradigm is going to shift to having your complete PC virtualized - this is the first step.
What in the world would I use it for, you ask? Examples? You could have a PC with an additional video card that is directly passed to the Guest virtual machine, so that it can have its own dedicated video. A network card that can now operate at full native speed, as it is completely controller by the Guest system. Or a hard disk controller card managed by your Guest computer. This opens the door to now have a completely virtual desktop experience, and native speed servers. It will be possible, over time, to have a completely virtual desktop without the current issues with heavy graphics/ 3D systems.
The code for this has been in the cooker for several months. This is the first inclusion in a “release” of KVM, so expect continued improvements. I believe at this stage it is supported only with Intel’s Virtualization extensions (which means the AMD PC I have wont do it, but the Intel one will). I’ll double check on that and update that here with the requirements.
I am looking forward to testing this out with my MythTV (Tivo type software under Linux) system in the next few weeks.
Read more of this article »
Posted by on October 28, 2008 under Uncategorized |
UPDATE: Apparently, the Codeweavers website is getting hammered due to this free offer. Click the link below to connect DIRECTLY to the registration page. Once registered, you are locked in - but you only have until midnight on 10/28 to register.
Its true! Codeweavers is offering Crossover for Linux and Mac for free (including support) - but for today only. Check it out at Click Here to Register. Crossover is an application that allows certain Windows applications (including games) to run natively on Linux and Mac. I’ve already got my copy.
Read more of this article »
Posted by on October 27, 2008 under Uncategorized |
As I mentioned to some of my peers at the Round Table, I think Microsoft will eventually dominate the Virtualization market, and quickly start taking big chunks of VMWare’s customers away. Here is some evidence: HyperV 2.0 Features Announced.
Now, if you know me, you know I am partial to FOSS (Free and Open Source Software - not necessarily free as in price), and Microsoft is not FOSS. I tell you that as a disclaimer, so you know I am not a Microsoft fan trying to sell you on HyperV. In IT, it’s a Microsoft world, so I have to study it, understand it, and use it. I have been working with Virtualization in production environments for about 5 years now, most recently testing the viability of ESX and HyperV for our production use.
To the uninitiated, it is easy to pick HyperV. I have already seen engineers, who would not otherwise consider virtualization, move to it ever since HyperV was made available as a part of the 2008 OS. It makes sense. With just a few simple clicks, suddenly you can run multiple OSes on your PC or server. Dead simple. It is also easy to use, and has some useful features already included. The management console, snapshots, and import/export tools are of great value, and I would argue that it’s Quick Migration (as opposed to VMWare’s VMMotion or KVM’s Live Migration) is practical and meets almost all requirements.
To the better informed, a closer look is needed, and that is what I have been doing for the past few weeks. I can tell you straight away that HyperV suspiciously looks like Xen… a lot (With Windows 2008 as Dom0). An interesting footnote: Microsoft’s longtime buddy Citrix purchased Xen Source last year. Theoretically, that purchase would allow MS to obtain a private license with Citrix to use Xen code outside the open source license under which it was developed, and under a different license. I can also tell you that side by side HyperV doesn’t match up as well with ESXi. Even with similarly configured guests with identical host hardware, the tests I performed showed that ESXi was plain faster (on a side note, KVM was faster than both). And the ESXi management features are impressive with the detail that you can manage your Guest VMs. ESXi does binary translation, whereas HyperV requires virtualization extensions. This means that ESXi will run on older hardware as well.
So if ESXi is technically better, than whats the deal with HyperV? For evidence, see the above referenced article. Microsoft will continue to work on HyperV, and will very quickly include all the features that the Enterprise requires (read that as all the features that VMWare has). On top of that, it is included in their OS (akin to how Internet Explorer took over), and costs almost nothing to install it. To the average IT person, this is a no-brain-er, and is a VERY easy to path to virtualization. I can tell you that when I first started Virtualization 5 years ago, if HyperV existed and was as easy to install (and as functional) as it is today, we would be all HyperV by now. That is saying a lot, coming from me. And the performance difference, while noticeable, wasn’t so great as to exclude HyperV from consideration.
I hope VMWare can come up with a good way to compete with this juggernaut. I think in time KVM will silently become the standard, especially in large production data centers, much like Apache and Linux are today. But for other corporate uses, VMWare is going to have to complete heavily with HyperV.
For now, for us, KVM is our standard VM platform, and we will start using ESXi to fill in some holes (especially with older equipment). By comparison, HyperV just doesn’t meet our requirements… yet. But I have seen it already working well for others in production environments, and can only guess at what the future holds.
Read more of this article »
Posted by bitbud on October 3, 2008 under Bitbud Blog |
SAN for ALL!
The paradigm has shifted (some time ago), and centralized storage is now a requirement for any organization to most efficiently run their infrastructure. The ability to pool your storage resources, especially as data storage requirements explode, is invaluable. No longer being tied to how many hard drives a single server can hold, but instead having expandable storage easily accessible via a network. Today, iSCSI is the standard bearer (sorry FC, AoE), and many organizations see the need for implementing it. However, the most common roadblock to implementing a SAN…
$$$ (cost)
There are other impediments, but cost is easily the biggest. It almost hurts to read about such great technology, to work with it in the business world every day, but not be able to afford it for your church. The features and the capabilities that are gained from a well implemented SAN add so much value to IT, they cannot be ignored. When IT works more efficiently, that helps them fulfill their role to support the ministries of the Church, which in the end is all that matters.
The cost factor is especially true for a small church (like mine), where there is no IT budget, where the infrastructure is built almost exclusively on donated, older computers. In those situations, the necessity to be good stewards of limited resources is highlighted. For a church of any size good stewardship is important, but for a church with no financial resources to contribute to the cause, it seems as there is no opportunity. But that isn’t the case…
This is for those church’s who see the need for the technology, and have the time, but almost no resources to devote to the effort. This is also for those that see the need, have the time, and the resources, but want to save some money, and gain a greater level of understanding, experience, and flexibility - the typical DIY-er. You too can have a SAN, with every feature available to you in commercial SANs, for little to no cost. The only thing you sacrifice is performance - at least for the SAN that costs nothing. However performance can be improved to be on par with commercial equivalents for minimal amount of cost.
I’m going to break this down into several posts covering multiple options for configuration, features, costs, and performance. Let me start with an example:
At my church, I recently implemented a new SAN for $476, using two donated PCs. You could get by for less $$ if your PCs already have SATA hard disks of the capacity you want, but these were oooolllllddddd computers, so some minor upgrades were needed:
- 4 * 500GB SATA II drives @ $80/ each
- 2 * SATA II 4 port @ $18/ each
- 4 * Intel Gigabit PCI@ $40/ each
So - what did we get for all this?
- approximately 1/2 TB of disk space
- RAID 1 (mirror)
- FT/ HA (fault tolerant/ high availability)
- Dynamic resize
- Snapshot
- multi protocol (we use NFS and iSCSI, you could also use AOE, CIFS, etc)
- encryption
- cuts your grass
- makes your coffee
- …i might have forgotten something
How does it work? The two PCs are each running 2 500GB drive in a RAID 1. They are also connected to each other in a network RAID1. Using HA, they are providing network services(NFS, iSCSI) in a primary/secondary fashion. Dynamic resize and snapshots are provided via LVM, for the NFS shares I used XFS.
The FT/HA adds a bit more complexity, and may be overkill for many. The rest of the features though are important. An alternative to HA would be to simply use the 2nd PC as a backup system of the first, using simple replication.
These system were put in place to support the virtual servers that will be running all the back end systems.
In the next post I’ll go into the details of installing and configuring iSCSI on Ubuntu.
Read more of this article »
Posted by on September 25, 2008 under Uncategorized |
UPDATE 2008.10.03:
So it looks like Travis was right, and an Outlook plug-in is needed - which means this system isn’t 100% compatible, although the ActiveSync part looks interesting. That means the only100% solution I know of is still Post Path. It just isn’t open source. If Cisco would find a way to GPL it, they would literally TAKE OVER the market. Maybe one day they will.
Original Post:
So someone FINALLY released a 100% MAPI compatible (read - Exchange compatible) system under an open source license. Zarafa. At first read, it appears to offer full ActiveSync support, and Outlook over HTTPS as well. The limitation appears to be in the number of Outlook clients that can connect via MAPI, unless you purchase one of the higher-end versions.
I’ll post an update after further evaluation.
http://zarafa.com/?q=en/content/community-0
Other 100% MAPI compatible alternatives include PostPath, which was recently aquired by Cisco. But they aren’t (yet) open source.
Read more of this article »
Posted by on September 19, 2008 under Uncategorized |
I ran into a problem the other day… too many downloads of a large VMWare image I had shared. It swamped my connection and made the server inaccessible. So I had to quickly put in a bandwidth limiter, and thought I’d share how easy it is to do:
I am using mod_bandwidth. There are several other Apache2 modules for managing bandwidth. This one is a great quick fix. In fact, I usually install this by default, but unfortunately forgot to on this website - until my bandwidth was maxed. I highly recommend installing something along these lines to protect your system from this problem.
My system is Ubuntu Server and Apache2
This is simple to implement:
- Grab the latest version of the source code
- Extract and compile the Apache module
- change apache2.conf
To begin:
Find the latest source code download link at: http://ivn.cl/#bandwidth Currently it is version 0.8
In a Terminal windows, run these commands in a temp folder:
sudo su
apt-get install apache2-threaded-dev
cd /tmp
wget http://ivn.cl/files/source/mod_bw-0.8.tgz
tar xvzf mod_bw-0.8.tgz
cd mod_bw
note: you may get an error after running this next command - you can ignore it
apxs2 -i -a -c mod_bw.c
nano /etc/apache2/apache2.conf
add the following to the top of the file
LoadModule bw_module /usr/lib/apache2/modules/mod_bw.so
BandWidthModule On
BandWidth all 1000000
MinBandWidth all 100000
ForceBandWidthModule On
This will limit the apache server to 1 Mb of bandwidth with each connections getting at least 100k
Read more of this article »
Posted by on September 11, 2008 under Uncategorized |
“Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe, in order to assure the survival and the success of liberty.”
– John F. Kennedy
For about a year after September 11th, 2001 this quote was in my signature at the bottom of every e-mail, regardless of who it went to - a friend, a customer, anyone.
As I sat in my car this morning talking to my wife, I lamented that so many have already forgotten, or pushed into the back of their minds, the events of this day. The very real threat that exists in this world from those that hate America and what America has stood for - a country built on the principles of God’s Word (often called Judeo-Christian values). A country that has been blessed, has prospered, and who’s citizens share that blessing with others in the world, more so than any other country.
Like everyone else, I remember exactly where I was 7 years ago as though it happened today, even if I can’t recall what I ate for lunch Monday. I recall the odd feeling, simply trying to understand what was happening, “Why has ANOTHER plane flown into the building?” The abrupt realization that we were like children, who’s innocence was suddenly broken, and our view of the world around us would never be the same.
I also recall where I was on another day, November 7th that same year. I was working in Chicago. That evening I was in my hotel room finishing some client notes from the day, with the CMA Awards show on the TV. I stopped suddenly when Vince Gill announced that Alan Jackson, my favorite country singer, was coming on to perform a never heard before song. He delivered the song in an appropriate way that only Mr. Jackson could, quite, humble, just him and his guitar (reminds me of my dad). The words spoke to me, as they did to millions of others.
We have to watch out for complacency. Certainly on this day, I think of the complacency that might make us think we are no longer vulnerable to attacks of this nature, that it won’t happen to ME. But we must also be on constant guard for complacency in all areas of our lives, with ourselves, and how we direct the way we live… complacency in the attention we provide to our spouses, our children, our Faith. They require our constant attention. My dad once told me that life is a struggle, that you must battle every day against the wickedness of the flesh. I know what he spoke of, and it comforted me to know that this man, my dad, the man that has earned my love and respect, above all other men that I have known in my life, confided in me that he too, we all, face this battle. As my dad always does with such ease, he was speaking from God’s Word, where even one such as Paul struggled every day, and was not afraid to admit it.
I have struggled with complacency, and reflecting on this today I know that I must work each day going forward to lean on the power of the Holy Spirit within me to win this fight. Sadly, I do not find myself complacent about worldly things, which are not important as they will pass away, but am too often complacent about the important things that live forever - my wife, my son, my church. I must endeavor to stand on Gods Word, actively, everyday, to spend my full effort building Gods kingdom in my family, my church, and the world around me. It is ironic that as I look to the past today to address my own complacency, God’s Word says that I must move forward by forgetting the past, and focusing on what I can do now, and in the future. This is a blessing, being released from our past, our sins, which enables us to pursue the best that God has in store for us. I don’t have to waste any more time with sadness over the past, but am freed to focus on the Hope of today, and the future. But not to forget that it is work, and must be worked out everyday.
As I sat in my car this morning talking to my wife, I lamented that so many have already forgotten…
And as I spoke those words to my wife, I noticed the flag in front of our office building this morning - at half staff. Not every one has forgotten…
Hope is not lost, when our Hope is in Christ Jesus.
References:
Romans 7:14-25
http://bibleresources.bible.com/passagesearchresults.php?passage1=Rom+7%3A14-25&version1=51
Philippians 3:12-15
http://bibleresources.bible.com/passagesearchresults.php?passage1=Philippians+3%3A12-15&version1=51
Ephesians 6:10-20
http://bibleresources.bible.com/passagesearchresults.php?passage1=Ephesians+6%3A10-20&version1=51
http://www.cafonline.org/Default.aspx?page=12183
http://www.christianitytoday.com/tc/2003/001/14.14.html
Read more of this article »
Posted by on September 4, 2008 under Uncategorized |
Red Hat announced today the acquisition of Qumranet, the inventor and maintainer of KVM: http://www.redhat.com/promo/qumranet/
Red Hat has been involved with the ongoing efforts to develop and maintain KVM. I think this will give additional focus, resources, and credibility to the KVM project. Red Hat’s virtual management project, oVirt will probably pick up the pace as well.
So long as Red Hat keeps development of KVM as free and open-source, this should be a big plus. I don’t know why they wouldn’t.
It’s been clear to me for over a year now that KVM was the future of virtualization, that VMWare and Xen would fade as the Hypervisor becomes a commodity. Ubuntu moving to KVM as it’s primary platform for virtualization was the first validation, and now Red Hat. KVM already has a broader set of capabilities than ESX and Xen. It’ll blow the doors off of virtualization with the upcoming PCI passthrough capabilties (more news on that to follow).
I’ll keep you apprised of what I see going on in the developer community for KVM
Read more of this article »
