Cisco E2000 Router is solid when flashed with DD-WRT [Networking]

Over a year ago I owned a Linksys WRT-54G V4 router configured as the main and a Netgear WNR8348 configured as a repeater bridge. Both running DD-WRT on wireless G. The solution was rock solid.

After several months, I decided to go the N route and got a Trendnet TEW-637AP and sold the Linksys. A very bad move. The Trendnet would not work as a repeater bridge (or client bridge), so I installed it as main router instead. The Netgear WNR8348, then configured as repeater bridge, started dropping packets and lost connectivity consistently.

Later I replaced the Netgear with an Asus RT-N12 and gave it away. I ended up in worse shape as the Asus lost connectivity every 15 minutes when copying large files; Netflix streaming was just impossible. I tried all kinds of configs (N, G, mixed, 20 Mhz, 40 Mhz, different power settings, you name them). It just did not work.

I was frustrated to the point of thinking about running physical cable but did not execute as it was going to be a very challenging task.

Last attempt to migrate to Wireless N:

I decided to give it a try to a pair of Cisco E2000 routers to replace my repeater bridges which got flashed with DD-WRT as soon as they arrived. I was really surprised with the positive results they gave me after transferring ISO files over wireless, to the point that they were maxing out my PC LAN port consistently. The only change I made was to lower the TX rate to 50 mW (default is 70 mW). The main Asus streaming wireless router is configured to serve N Only connection at channel 7 (2.4 Ghz) and Turbo Channel Width (40 Mhz).

Maxing out the LAN port

Maxing out the LAN port

From now on, I will stick with Cisco or Linksys for my networking needs.

This is how my home network is configured currently:

Home Network

Home Network

Migration to 2008 R2. Not as easy as Copy & Paste [Performance]

We have gone through several migrations already, mixing and matching sources (SQL 2000, 2005, X86, X64, Enterprise to Standard, etc). We now got most of our databases running under SQL Server 2008 R2.

In every instance we have found performance issues related to HyperThreading, bad plans, missing registry key or outdated iSCSI drivers. We have reached a point where we are now ready to analyze and solve the challenges soon after the migration has been performed.

We recently migrated a core DB, from 2005 to 2008 R2, from X86 to X64 and from Enterprise Edition to Standard Edition. System was effective but the application was sporadically timing out. After digging through the logs, collecting info based on server side traces, and using Adam Machanic’s sp_whoisactive tool, we found the culprit. Eight services pulling data using 1 stored procedure was bringing the box to it’s knees. With updated stats, better hardware and more memory available, we never expected this to happen. But it did.

We added an index and narrowed the scope of a where clause inside the stored procedure. The procedure went from ~30 mins and ~100 million reads to 10 seconds and ~15,000 reads.

Small changes, huge differences. The key is to spot the issue, understand and work it around. Then schedule a production push and QA the process.

Reads out of hand

Things look very good now.

Your Smartphone. What if you lose it? [Security]

Ever thought of that scenario? Not yet? Better start thinking about it now. If you work for a large corporation you might already be backed up by an enterprise level security system, but if you are not, then it’s time to get something in place to protect your information.

Work/Personal email, text messaging, sensitive documents, Facebook, Twitter, personal banking applications; you name them. An stranger can get access to them very easily (with banking application might be trickier, but at least they can try).

I use two products to protect my Android based phone in the case it gets lost or stolen.

  1. Protector, an application that allows to setup a pin to access certain applications (fully configurable). This is very useful when you want to lend your smartphone to a friend for them to search but not allow them to open your email inbox for example.
  2. Lookoput (available for Android, Windows Mobile and Blackberry). Protects your phone from viruses and backs up your information to their systems (calls, sms, etc). If you pay you get the premium options to locate, remote lock and remote wipe. These last 3 are the most important features for me.
Lookout

Lookout

There are several other products out there you can try yourself.

Good Luck!