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Some future predictions

WhatsApp sold for 19B! SMS has changed. Communication has changed. Everything is coming back to data and telcos only has Internet/data plan to charge. Before they have voice (long distance, international), text, data. Now it’s only data that matters.

I see these as hot: Data Compression and Caching/Optimization as they become more and more important to reduce the bandwidth while delivering more. Serve more with less.

HDD to SSD and Windows 8.1

Couple issues
– Acronis True Image HD shipped with Crucial M500 does not work with Windows 8 and GPT partitions. It will not see the HDD and therefore cannot clone it. Need to use a newer version, like Acronis True Image 2014 Premium
– ATI/AMD Catalyst 7730 driver crashes in Windows 8.1 so when it sleeps and wakes up, it will crash and do a hard reboot. Solution: download the latest “beta” driver from ATI/AMD

– Working drivers: ATI/AMD graphic driver v 13.250.18.0 (11/7/2013) and Intel Wifi v 15.10.3.2 (8/22/2013)

LVS, director and SSL cipher

Some odd behavior, handshake with a specific cipher passed with the director but not when handshake directly with a realserver.

openssl s_client -connect VIP:443 -cipher EDH-RSA-DES-CBC-SHA
openssl s_client -connect VIP:443 -cipher DES
=> Connected

openssl s_client -connect RIP:443 -cipher EDH-RSA-DES-CBC-SHA
openssl s_client -connect RIP:443 -cipher DES
=> No connection

Asus Router – Port Forwarding

Caused me some grief for its lack of notification in the UI. I enabled uPnP on the IP camera and it showed up in the port forwarding log but it could not be accessed. Port is open. It turned out that I need to also explicitly enable Port Forwarding (and leave the it other settings empty). It’s good for security but at least it should have a log to show why it’s not working properly.

Gravity drip irrigation

I’ve been setting up a system of cheap drip irrigation for a remote location. Here are the facts and criteria

  1. Remote, no electricity, off-grid
  2. Water from well, well pump run only by generator
  3. Multiple trees
  4. Drip time before refilling (about one per week)
  5. Hot summer (80-100F), wet mild winter
  6. Windy site, full sun, no shade

Here is the setup so far:

  1. 1/4 tubing
  2. 1/4 tubing w/ 1/2GPH emitters at 6″/12″ spacing
  3. 1/4 fittings (tee, connector)
  4. 1/2 tubing
  5. 1/2 fittings (tee, connector, cap)
  6. mini sprinklers
  7. 1/2 GPH PC/non-PC emitters
  8. Trash cans (32G), many, cheap at OSH $10/each, this acts as the rain barrel, container
  9. 8x8x16 Concrete blocks ($1.48=>$1.54 at HomeDepot)

Basic steps for a single emitter

  1. Drill trash can to connect out to 1/4 pipe with valve
  2. Connect 1/4 tubing with 1/2GPH emitter at the end
  3. Place water container on top of concrete blocks to create pressure
  4. Place emitter at base of tree

Other setups:

  1. Single tree, single barrel
  2. Single barrel, several emitters

Problems encounters:

  1. Run out of water from a single trash can too quickly
  2. Time to manually water and refill containers

Google Drive, XAMPP, MacBook

  1. Rename “Google Drive” to one without space. Example: GoogleDrive to avoid issues
  2. Move app to that folder: /Users/xxx/GoogleDrive/htdocs/MyApp
  3. Edit XAMPP etc/httpd/extra/httpd-vhost.conf:
    <VirtualHost *:80>
    DocumentRoot “/Applications/XAMPP/xamppfiles/htdocs”
    ServerName localhost
    </VirtualHost>

    <VirtualHost *:80>
    DocumentRoot “/Users/xxx/GoogleDrive/htdocs/MyApp1/webroot”
    ServerName dev.app1
    </VirtualHost>

    <VirtualHost *:80>
    DocumentRoot “/Users/xxx/GoogleDrive/htdocs/MyApp2/webroot”
    ServerName dev.app2
    </VirtualHost>

  4.  Map custom domain to localhost in /etc/hosts:
    127.0.0.1 dev.app1
    127.0.0.1 dev.app2

TL-WR1043ND, DD-WRT and NetGear WNDR3700

Setup 1043ND (DD-WRT flashed) as wireless repeater for WNDR3700 (stock firmware). First set it up as Client Bridge, make sure it works. One major gotcha is DHCP, did not flow through initially so I thought it wasn’t working when a static assignment showed it was bridged properly. Then add the virtual interface as AP to access it wirelessly. Still testing, some links:

http://www.dd-wrt.com/wiki/index.php/Client_Bridged
http://www.dd-wrt.com/phpBB2/viewtopic.php?p=630485
http://blog.jeffcosta.com/2011/09/29/create-a-wireless-n-bridge-with-2-inexpensive-tp-link-routers/
http://www.dd-wrt.com/site/support/router-database

Retina Macbook Pro – First impressions

Got mine 2 days ago. Here is what I like:

  • Fast! Open apps almost instantly thanks to SSDs
  • Retina is very sharp, almost too sharp and many apps or logos turn blurry because of the high resolution. Viewing photos from D800 is fantastic, very sharp and the colors are extremely vivid. Love it!
  • Illuminated keyboard, very nice when the environment is a little bit dark or you don’t have enough ambient light
  • Lighter than my old unibody MacBook 13″ (no optical)
  • Mail 6 is definitely better than older Mail on my old MB, very easy to setup and threaded like Gmail.

Cons:

  • Upgradability is low. I knew this so started with a better CPU and more RAM (16G). Hopefully it lasts me a bit longer. I think Apple understands this so upgrade pricing is decent and not too expensive.
  • No optical drive, I do need files from DVD from time to time. I guess I cannot have everything. It’s an okay removal and I still have other options for this.
  • Firefox is still blurry. This is a problem with Firefox, not Apple, so I’m switching to Chrome. Other older apps have blurry text (eg: KeepassX)

Overall, it’s a great machine and I think Apple is doing a great job going for the ridiculous Retina resolution. Other vendors will have to get there, just a matter of time. They’re in a great position: they control the price and they control the market share. What else do you ask for. And they keep going for the edge. Too bad I don’t have any AAPL 🙂

Nice replication setup

If you have a chain replication: A=>B=>C. If B is out of sync for some reason, C will be out of sync and you need to rebuild. The nice thing is that when B is rebuilt, it automatically rebuilds all its slaves (C1, C2, C3, etc.) because B&C are still in replication, the DROP IF EXISTS and those INSERTs will run as normal, which is very nice because you can have a few secondary head slaves (B1, B2, B3) and then hundreds/thousands of real slave (C1,C2,C3,C4,C5). They will cascade data down the chain when you only have to rebuild the secondary masters.

Ideas

Vision: an app that can identify what’s in a photo. Examples: use your mobile phone to capture an unknown flower and it tells you what kind of flower. Applications: plant, insect, bird, fish identification. If it does not know, it uses crowd-sourcing for identification (forums/community input). Anyone knows of such an app?

Vision: virtual organizer of real things. You put your physical items into virtual bins and the software will automatically identify, categorize. You can search, find the items. Think “computer file folders” but with real items (golf clubs, Christmas ornaments, garden seeds, paperworks, etc.) Anyone knows if anything like this exists?

Vision: plug a USB into your head to read a book. Lose the fun of reading, gain the speed of obtaining information