RoR IDE?
I’m sold, use Netbeans 6+ for Ruby on Rails development.
A good book on the subject (get the 2nd edition)
One-Time Passwords
Came across an old and interesting solution to login security … one-time passwords.
OTPW – A one-time password login package
Rails for everything?
According to this article, Rails isn’t the greatest thing since sliced bread or fire. Here’s the summary:
- Heard that RoR was the quickest way to a production web site. Decided to use it.
- Hire ‘’a GREAT Rails programmer’’
- Spend 2 years trying to create the web site; used all sorts of back door Rails hacks to get it working some. Entire industry changes directions.
- Never actually finish – give up.
- Quietly start hacking using a language that he knew, PHP, alone, … 3 months later, done.
What did he learn?
- whatever language you already know is probably a better choice.
- The ideas that Rails provides – Model, View, Controller are really good.
- OOP is really Good – thanks Ruby
- If you find yourself fighting with Rails, drop it and use the language where you don’t have to fight.
A good book on the subject (get the 2nd edition)
Microformats
Microformats are a fantastic idea!
Think of them as a tiny subset of information to be exchanged. Some of the most popular micro-formats include vCard, hCard, hResume, hCal, … anyway, you get the idea. Whenever you want to share the details on someone, some event, or just a contact – micro-formats are probably the easiest way.
When ever you create a new web site, thing about the pivot use of your data or user data. How can someone else use this data? How can the user re-use their data someplace else? Is there a way/desire to connect data from your site to another site(s)? If there is, find a microformat and use it!
Ruby on Rails - huh?
Ok, so I’ve been doing a bunch of research on Ruby and the Rails framework. Comparing all the things that an enterprise would care about:
- Deployment complexity
- Overall Maintainability
- Ease of development – MVC by default
- Availability of development, deployment, and testing tools and toolkits to make life easy
- Testing (TDD would be nice)
- Performance
- Profiling – finding slowdowns
- Cross Platform issues
- Web server compatibility
- Version Control Integration
- DBMS Support
- Cost for all the items above
- Others
Anyway, the short version seems to be that Ruby on Rails is an ideal solution for reducing time to deployment and maintainability of web applications for small user community apps. It won’t stand up to slashdot traffic. If that’s what you need, java and a good technical architect will be useful to ensure your app scales. Application performance is up to 50x less than the same Java application, but much of that is due to Rails and ActiveRecord generalizations (which is part of the reason why Rails is so quick to deploy apps with!).
Things I love about Ruby on Rails: DB and Models are generated automatically. Migrating DB upgrades and downgrades are built in. MySQL and SQLite3 support is built in. Very short time to usable apps. Built-in Development, Test and Production environment and promotions by default.
Things I hate about Ruby on Rails: ActiveRecord access is slow. No DB indexes are automatically created. Ruby language – oh yah, I need to learn yet another language (add this to 20+ I’ve already worked in). FCGI is the best way to deploy production apps?
Ready to get started? Only have MS-Windows?
A good book on the subject (get the 2nd edition)
GPS Application
The Amazing JDPFu.com GPS Application. It is simply uncanny and will tell you exactly where you are!
Build Your Own RAID 5 Array
October 2010 Update
This article has been getting hit a bunch, so I thought an update might be helpful. The array built below is still working nicely. I’m still using it as a NAS, NFS, CIFS Server, Samba Server, DLNA server and for protected storage to the local machine. The local machine is now a Core i5-750 with lots of RAM that also runs a few virtual machines. The machine also runs compute processes since it has plenty of excess CPU and excess RAM available.
The hardware RAID card was removed when the motherboard was replaced. The new CPU/MB has 6 SATA connectors internally, so those are being used. No complaints. For more information on Migrating Software RAID.
The Infiniband cable just works and has never had any issue.
The machine has an Intel PRO/1000 NIC ($25 @ newegg) to be certain of reasonable GigE network performance and possible future compatibility with VMware ESX/ESXi.
I’ve tuned both the disk cache and network buffers available to improve performance for large file transfers.
I’m considering adding AoE, ATA over Ethernet, and iSCSI servers to this machine so others on the network can access the storage too. AoE seems like a more efficient solution available for block storage access.
The RAID5 setup hasn’t had any issues in years. No dropped disks due to vibration or any other issues … besides being nearly full most of the time. I guess that’s the way of all storage.
Original Article Follows:
Ok, after months of research and finally finding all the parts at "reasonable prices", the array has been ordered, delivered, built, tested on multiple OSes and brought into production use. I’m mostly happy and will outline what I’d do differently this time.
Parts:
- Addonics Array w/ Infiniband port – $139
http://addonics.com/products/raid_system/mst4.asp
http://addonics.com/products/raid_system/images/amst_front_large.gif - Addonics Infiniband Cable – $80
http://www.shopaddonics.com/mmSHOPADDONICS/Images/aaib4c150.gif - Addonics Infiniband 2 quad SATA bridge (inside computer) – $50
http://www.shopaddonics.com/mmSHOPADDONICS/Images/ad4saml-pci.gif - 4x Seagate 320GB perpendicular drives (running quiet and cool) – $400
- Promise TX4310 4xSATA2 Hardware RAID PCI card (RAID5 capable) – $115
http://www.promise.com/product/product_detail_eng.asp?segment=RAID%205%20HBAs&product_id=165
Step 1. Put the 4 drives into the array and connect all the power and SATA2 connections.
Step 2. Connect the Infiniband cable to the array.
Step 3. Install the Infiniband-2-SATA in the computer; leave room for the SATA cables that will waste 2 card slots – yes, this design sucks. I connected the SATA cables before installing this inside the computer.
Step 4. Install the Promise card in the computer, connect the SATA cables from the converter to the RAID card. Test the drives with Spinrite.
Step 5. Fight with the Promise drivers (not included b.c. they are complete idiots), you’ll need to update the firmware, windows drivers and web management software. Promise doesn’t include any of this software on the CD that comes with the card. Worse, they use a proprietary extension to the ZIP format that only a current WinZip supports. After all the zipping is done, they saved 4K from a self-extracting EXE. Stupid, stupid. Long story short – HW RAID works under WinXP, not Ubuntu Edgy. Promise support answers email with – that’s an old card and we don’t support that kernel.
Step 6. Curse … a lot.
Step 7. After spending 3+ weeks fighting to get HW RAID working under Linux, give up and use software RAID – ‘mdadm’.
Step 8. Good news – under current Linux kernels, the Promise controllers are recognized as JBOD controllers, so software RAID can be used.
Step 9. Partition each drive with an "autoRAID filesystem", use mdadm to create a RAID5 array (chunk size 128K), mkfs -t jfs /dev/md0 (or whereever the mdadm tells you the device is located), use mdadm to pull the array info needed for the /etc/mdadm/mdadm.conf file, update the /etc/fstab with the /dev/md0 device and mount point, create the mount point, mount /dev/md0 /raid5, and start using your array with some test data.
Step 10. reboot your box and verify that it comes up and the array is automatically assembled and mounted. If not, start reading the man pages.
What I would do differently:
- Don’t buy Promise RAID card (I really wanted an PCI-X1 card anyway)
- Pick a hw RAID w/ XOR engine that is supported by the Linux kernel (no proprietary drivers without complete source).
- Don’t use Infiniband cables. Don’t get me wrong, the cable is great and solid connection. My problem is the $80 for it and the $50 for the converter into SATA2 connector I needed. I’d try the eSATA-MP cable next time and find a RAID card that can accept it. There are very few Infiniband RAID cards (I gave up looking). The converter design really bugs me. They should have "end-mounted" the sata connectors, not side-mounted them.
- Don’t bother with LVM2 unless you really need it. I learned this lesson a few years ago and I won’t make that mistake again.
- Use either XFS or JFS file systems. These are the highest performance general purpose file systems that are included with standard kernels. Don’t use a file system that isn’t part of your normal kernel – another lesson I learned a few years ago. I really would like to use ZFS, but it isn’t included in any kernels to my knowledge. I’ve been a fan of JFS since 1996 running AIX. I’m still a fan, it has never let me down. Some dated file system benchmarks. Some newer RAID benchmarks that show hw raid is often faster. However, here’s an article from a Linux kernel developer as to why software RAID should almost always be used for internally connected disks.
- Run Spinrite on all drives before making them part of any RAID config. Best to find any issue before getting everything up and RAIDing.
- Double check all your connections – a loose SATA connection in the array caused me to waste about a week assuming the Promise controller was bad hardware, not bad software.
A few links:
http://addonics.com/
http://www.newegg.com/
http://www.pricewatch.com/
http://www.linuxjournal.com/article/8874
http://www.linuxquestions.org/questions/showthread.php?t=387769
http://www.howtoforge.org/archive/2007/1/14?s=988d6534035fb8aea0a7793bb3318eb7&
http://www.linuxdevcenter.com/pub/a/linux/2002/12/05/RAID.html
