Custom Nagios Scripts

If you are into systems and datacenter's and are using Nagios as your monitoring tool then this article will be useful for you.

During my stint with one of the organisations I worked with, there were situations where we need to perform certain tasks like

- Enable / Disable Notifications for hosts
- Enable / Disable Notifications for all the services of a particular host.
- Deleting Scheduled downtimes for services.
- Deleting Scheduled downtimes for hosts.
- Disable Notifications for host group
- Enable Notifications for host group

What you need to do is

• Login with root / Nagios user
• Ensure that the nagios command file is at the below location :  /usr/local/nagios/var/rw/nagios.cmd
• If its not there, find the appropriate location and edit the scripts accordingly.

The scripts can be found here
Link to scripts

Your feedback is welcome and let me know incase it doesn't work for you.

ASUS Transformer TF300T not powering on

Incase you own an ASUS Transformer (probably should be applicable on other android tabs as well) , and wondering why your tab doesn't power on when you left it unused for a while, then this is how you can fix it.

You need to follow the hard reset procedure to get it back alive.

Steps to reset :

1. Press the power button (Top Left)
2. Press the volume rocker (down) which is on the Left side of the tab when you are looking at the screen.

Keep holding 1 & 2 for a couple of seconds, and then you should soon see a booting screen of ASUS showing up on the screen.

I am not sure of why this happens though, but my understanding is that it happens generally when there is some corrupt data loaded in the cache of the tablet.

Hope this helps.

Understanding Android / S2 Camera Settings

Below is what all I learn't & read exploring different options in my Samsung Galaxy S2 (ICS).

Sharing it with you guys as this might be helpful. Let me know if you have anything more to share as tips and tricks or also if you have anything else to add below.

Below are some options which are used in S2 phones / rather are common with most of the camera's so are basics :

1. ISO Settings  : Higher ISO setting in darker Light, you get faster shutter speeds.
2. Auto Contrast : Should be ON when you are capturing pictures in bright day.
3. Outdoor Visibility : Should be ON when you are capturing pictures in bright day.
4. Exposure Value : Refers to the total amount of light that hits the image sensor when taking a photo. This can be tweaked as per you desire and experiment
5. Resolution : Keep resolution highest for high quality images, downside is the image size is more, but who cares, we already have alot of space on our phone ';-)
6. Metering : Metering is helpful if your subject is lighted differently than the rest of the shot, such as if your subject matter is in bright light while the rest of the shot is in shadows.
7. Tap To Focus : When shooting into a crowd or other busy backgrounds, zero in on your “target” to capture precise focus on your subject matter. Locking in focus with the green square indicator will also help you avoid blurry images.

Full HD Videos :

You might or rather would say I am sure many of the android users, specially on Galaxy S2, are facing issues creating full HD videos using the stock camera.

While making your video, you will see your video going blurred many times in between in dim light, the reason of this blurness is actually that the autofocus tries to focus back again and again in dim light.This lead to an intermittent blurness in the video, and frustration that you never get a clear HD video.

Samsung is aware of the issue, but still couldn't come out with a fix yet. I ain't aware if it did recently.

You can fix this by installing "lgCamera" app on your mobile, and use it over stock for recording videos. I tested it, it works fine.In fact the video quality, I found it better using this app.

Just try and post your experience.

Missing eth0

You might face issues that when you restart / clone / change nics of your linux box and run the ifconfig command checking interfaces, you will see eth0 missing.

The reason of this is that the old MAC address is cached by the network configurations in some distribution on linux..

The file which has the cached entry is  : /etc/udev/rules.d/70-persistent-net.rules
You can follow the below 2 methods to fix this problem.

1. Edit the above file, remove the old entry of "eth0" , change "eth1" reference to "eth0"
2. Move this file in /tmp as a backup, and reboot the system. [ You have a backup, incase this doesn't work,playing safe ]