Blog Archives

What no one ever tells you about cluster hardware redundancy

I was recently reminded about this, so I thought I’d post about it and share the knowledge.  I use mostly HP hardware, so in this setup, lets say we have two HP DL585 servers for use in a Windows cluster.  I also have dual fibre channel interfaces in each server.  Externally lets say we have two separate fibre channel switches.  For storage, its an MSA1500 external fibre channel SAN with over 1TB of RAID storage, partitioned for use in a cluster.  The MSA1500 has dual controllers and each controller has its own fibre chennel interface. 

To connect it all together, each server connects one of its two fibre channel interfaces to one physical SAN Switch.  The MSA1500 SAN controllers each get connected to a separate physical SAN switch.  The goal here is to optomize hardware redundancy and make this configuration as fault tolerant as possible.  But here is where the issue comes in. 

No one tells you that you need special software running on each node of the cluster to handle the hardware redundancy.  If you don’t have this software in place, what you will find is that Windows will see two SAN storage arrays.  One of them will be inaccessible since you can only have one physical connection active.  I had to call HP support and go through several explanations of what I was trying to accomplish with all the hardware redundance before I was told about the software I needed.  Its called MultiIO or “Multi Path IO”.  If you do a search on the HP support website, you will find HP MPIO Basic (there are two versions, basic is fine for most people).  Download this software and install on each node and amazingly you will find that things work much better.  From the documentation I saw, there is no indication of needing this software, but in this kind of highly resiliant configuration it is necessary to use MPIO to control the hardware redundancy. 

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SPAMHAUS services

I am impressed by the services offered by SPAMHAUS, their data feed service is extremely useful and effective and their spam stats are amazing.  If only we could find a way to just stop spammers alltogether.  Immagine the bandwidth that would be freed up on the internet, if all SPAM were eliminated.

Beautiful sunset

I’m sorry I don’t have a picture to go along with this post, but I could have had an accident trying to snap a picture with my phone… I was driving home last night heading east on I-4 and looked in my mirror to see the most beautiful sunset. The sun was large and firey orange and visible between a few highrise buildings in the distance. It was a beautiful sight on a crisp clear day and was really amazing to see. The sad thing is that it wasn’t even 6pm yet and the sun was already going down. Its tough spending all day in an office, you get up before the sun comes up, go to work, and come home when the sun is going down and then have no daylight left to play with the kids outside. Fortunately its only lasts a few months.

review – at&t TILT

I have had the TILT with at&t for about a week now. I have to say this is the best phone I have used to date. Here are some highlights of why I like this device..

1. Its sleek and visually cool looking, coloring is modern and glossy.

2. The weight of the phone is indicative of being well built, it feels sturdy and tough.

3. It has plenty of onboard memory; you can customize the device, install apps and have plenty of onboard memory left without the need of a storage card.

4. Onboard GPS radio is neat; this is my first phone with true onboard GPS. A perk is that both Google maps and windows live search work with the onboard GPS radio for free.

5. The speed of this device to a data network is amazing. Over HSDPA I can download at nearly 1mbps which is not bad, although this connection is theoretically capable of much faster sped, but it’s still way better than EDGE!

6. You can use this device as a wireless modem, so when you travel or go somewhere that doesn’t offer free internet access, you can connect over Bluetooth to a laptop and get on the internet for free using your phone’s data plan.

7. Windows mobile 6 pro seems much more stable and visually attractive.

8. Battery life is not bad, in one day I am only using less than 50% of the battery with normal to light usage.

9. You can be on the phone and receive e-mail and use the data connection at the same time. No longer does using the phone disable all other radios on the device. You can now get important e-mail while talking on the phone.

10. Mobility! I can browse the web, make a blog post, track my position with GPS, take pictures, connect to wifi, use bluetooth devices, conect to VPN, run Citrix applications and sooooo much more, all while on the go.

There is more I will post about this device later, but those are the main points…

The song of a parent

This is an amazing video, it so accurately captures the feelings of a parent with small children. I can’t say enough things about how much I like this video. You’ll just have to watch it for yourself. Video courtesy of YouTube:

Watches Second Star Wars movie – The empire strikes back

Last night we again found ourselves with some free time and got the kids to bed almost on time. We crashed on the couch and started watching the second Star Wars movie. This one was definately better than the first, there were fewer flubs and the acting, story and effects were better (in my opinion). Its funny looking back at the movie, and seeing all the stop motion effects and realizing that back in its day, this must have been what was considered awesome effects and animation. However, watching it today, its just not wowing as it must have once been. We may watch the third movie tonight, if time permits.

So far I find the story line of the movies interesting. Whats really amazing is how young Harrison Ford looks and sounds. Its been a long time since I’ve heard him talk to fast! 🙂

Perspective

I was reading earlier about police chases and came across several stories in the St. Petersburg times about how each time there is a crash fatality that was the result of a police chase, the police chase policies are criticized. What I find most amazing is the varying perspectives based on who you ask about these policies.

To the police, a law has probably been broken, they persue and attempt to apprehend the person involved. The criminal then has two options, stop and be captured, or flee and risk death or worse, hurt others on their attempt to get out of trouble.

When people are in a panic situation, logic and rational thought often go out the window. But it is indeed a selfish choice to attempt to outrun the police and risk others lives just in a pointless attempt to outrun the police.

I read a response from the family of a criminal who was killed by running through a dead end road and crashing into a large pile of sand. The family member said: “It would have never happened this way if they had not chased him, somebody should lose their job for that”.

Its funny how tainted a person’s perspective can be based on the circumstances. To the family member, they blame the police for chasing a criminal. Its NOT the faulf of the police that this person decided to run and rish other people’s lives. In the end it was his life that was lost, and others were injured.

Now maybe this is my hero complex talking, but to me its so simple, break a rule, face a consequence. People break the rules all the time, when something illegal is done its the job of the police to apprehend the person responsible and apply a consequence. As citizens under the protection of the police, it is our responsibility to cease and desist when persued by the police. Everyone knows how this works, and I’m sure they knew the risks when the broke the law. Without policies allowing police to persue criminals, (who often times have faster cars than police, or vehicles that can handle offroad terrain better than a police cruiser) crime would be a much larger problem. People would think that they could do anything and just run to get away with it.

Good people put their lives on the line all the time to enforce the law, protect the public, and give chase to criminals who would otherwise get away with their crime if no chase was given. If a person knows the law, breaks it anyway, and dies as a result of fleeing a police chase, in my opinion, the person fleeing has sealed his/her fate. They will either be apprehended anyway and face worse charges, or they will hurt other people and possibly lose their own life. Its just not worth it!

Granny gets lightning fast broadband!

WOW, amazing speed for a granny to read newspapers with! Check out the full article on yahoo.

Nice lightning show

As I sit at my desk on the 6th floor of my office building, surrounded by glass windows; I am getting a very good view of some amazing lightning striking all around the area. We are having some early thunderstorms today, and the lightning is frequent, long and really amazing.

Sarah's birthday plans

Today is Sarah’s birthday, she is now 7 years old. Or 7 blinks old as I like to call it. Time goes by so fast, it seems like yesterday that we were driving to the hospital explaining that Liz was in labor to the friendly cop who thought he’d pull us over for a safety light that was blown on my car! I can’t believe she is 7 now, she is so smart, and so beautiful and so amazing. She has gone from being my baby, to being my amazing 2nd grader! Sarah will start 2nd grade at the end of next month. We still don’t know where she is going to school, but need to start trying to figure that out. We are still hopeful that we will get the acceptance letter from Lewis, but if not, may have no choice but to send her to Follsum in Thononassa.

For her birthday tonight, we are going to give her the dinner of her choice, which tonight is Pizza from Pizza Hut. Its something Sarah and I both share, which is a love for a large cheese pan pizza from Pizza Hut. Sure its not as good for you as say, Papa johns, but we share a love for that pizza.

This coming Saturday, we plan to have family and friends over as they can make it, for a small get together and have food and dessert. I’d like to try to find something fun for her to do on her birthday as well, perhaps go to the park, or something before we have dessert…