Ubuntu, linux and networking

How Fast Is Your Processor – Super PI

B S Murali — Mon, 03 Mar 2008 16:20:20 +0000

One of the easiest and fastest way to measure your CPU processor performance in linux is to download super pi from ftp://pi.super-computing.org/Linux/super_pi.tar.gz

Untar the downloaded file and issue the following command:

./super_pi 20

Here is the output of my CPU:

—— Started super_pi run : Mon Mar 3 21:46:27 IST 2008
Start of PI calculation up to 1048576 decimal digits
End of initialization. Time= 0.360 Sec.
I= 1 L= 0 Time= 1.144 Sec.
I= 2 L= 0 Time= 1.312 Sec.
I= 3 L= 1 Time= 1.312 Sec.
I= 4 L= 2 Time= 1.332 Sec.
I= 5 L= 5 Time= 1.312 Sec.
I= 6 L= 10 Time= 1.312 Sec.
I= 7 L= 21 Time= 1.308 Sec.
I= 8 L= 43 Time= 1.324 Sec.
I= 9 L= 87 Time= 1.312 Sec.
I=10 L= 174 Time= 1.320 Sec.
I=11 L= 349 Time= 1.304 Sec.
I=12 L= 698 Time= 1.312 Sec.
I=13 L= 1396 Time= 1.312 Sec.
I=14 L= 2794 Time= 1.308 Sec.
I=15 L= 5588 Time= 1.304 Sec.
I=16 L= 11176 Time= 1.296 Sec.
I=17 L= 22353 Time= 1.272 Sec.
I=18 L= 44707 Time= 1.244 Sec.
I=19 L= 89415 Time= 1.164 Sec.
End of main loop
End of calculation. Time= 25.918 Sec.
End of data output. Time= 0.140 Sec.
Total calculation(I/O) time= 26.058( 0.816) Sec.
—— Ended super_pi run : Mon Mar 3 21:46:54 IST 2008

Post yours so that we can know many other fast processors around us.

Networking home: Configuring wireless router – II

B S Murali — Sun, 09 Dec 2007 16:36:35 +0000

In my previous blog we have seen how to connect and use two routers one behind the other. In this blog I will explain how to use the IP address range of adsl router for the PC/computer connected to wireless router instead of IP address range of wireless router. This means using adsl router’s DHCP server. This is like using wireless router just as an access point.

Lets refer adsl router as A and wireless router as W. Assuming you have read my previous blog “Networking home: Connecting router to router – I” and set up your home network in the same way, here goes the steps:

1) Open A’s router webpage. Enable DHCP server in A and issue the addresses in some range that does not include one ip address which will be used by router W. For example, the range of IP addresses given by A will be 192.168.1.2 to 192.168.1.35 and the IP address used by W will be 192.168.1.40. This is all. Rest of the settings required will be the ISP settings as mentioned in my previous post.

2) Unplug the WAN cable of W.

3) Now open W’s web page. Disable DHCP server in it. Configure WAN to any static IP. Say 0.0.0.0. If the router does not accept, give something like 192.168.111.2 with the subnet mask of 255.255.255.0 and gateway as 192.168.111.1. This will stop sending network traffic to WAN.

4) Set the static IP address of 192.168.1.40 to W’s LAN settings which does not fall under A’s DHCP range.

5) Save the settings.

6) Plug the out going LAN ethernet connection of A to any of the LAN port of W. This will make router A serve as DHCP server for anything that is connected to W. Make sure that nothing is connected to WAN connection of W.

Note: After all this setup, you should be required to restart the network in a sequence of A, W and then the PC/computer. Give a couple of minutes before starting each device.

That’s all. If you see the IP address of your computer now, that will display the IP assigned by DHCP server of A. i.e. 192.168.1.x

Here is a summary:

Router A                     Router W
   WAN: --> ISP modem           WAN: Empty ethernet
        Configured for ISP           Static IP with Gateway 0.0.0.0
   LAN:                         LAN:
     IP=192.168.1.1               IP=192.168.1.40
     Subnet 255.255.255.0         Subnet 255.255.255.0
     DHCP: Enabled                DHCP: Disabled
   LAN Ethernet Cabling:
     (1) <======================> (1)
		                  (2) --> PC1
		                  (3) --> PC2
		                  (4) --> PC3

Networking home: Configuring wireless router – I

B S Murali — Sun, 09 Dec 2007 14:37:29 +0000

Here I will explain how to connect wired and wireless router in a network in the simplest way.

I have an adsl modem/router supplied by my ISP and also I have a four port netgear wireless router for going wireless. Lets refer adsl router as A and wireless router as W.

Connecting them is easier than you think.

1) You connect the phone line coming from the phone line splitter to A and connect the PC to the ethernet output of A.

2) Open the router webpage (usually http://192.168.1.1. refer router user manual). Configure A with the ISP details like username, password etc. The connection protocol usually happens to PPPoE. Enable DHCP server if you want. Save and reboot and you should be able to browse the internet provided you entered the credentials properly.

3) Now connect the ethernet output of A to the input WAN connection of W and connect the PC/laptop to the LAN connection coming out of W.

4) Open the W’s webpage. Again, it could be http://192.168.1.1 (refer user manual of W). It could prompt you the problem of IP conflict with A and will automatically adjust it self to other IP range. If not, disconnect the connection between A and W and reopen the W’s webpage. Configure the WAN settings to an IP with in the ip range and subnet of A or configure to get it automatically if DHCP is enabled in A.

5) Open LAN settings page in W. Configure the IP address to some other range. Say 10.0.0.1. Enable DHCP server and done. Save and reboot if necessary.

6) Connect A and W if you disconnected in step:4.

You should be good to browse through the internet. You will be get the ip range of W which would be 10.0.0.x.

And this is how it looks now:

Router A                     Router W
   WAN: --> ISP modem           WAN: Static or dynamic IP with Gateway 192.168.1.1
        Configured for ISP
   LAN:                         LAN:
     IP=192.168.1.1               IP=10.0.0.1
     Subnet 255.255.255.0         Subnet 255.0.0.0
     DHCP: Enabled/Disabled       DHCP: Enabled
   LAN Ethernet Cabling:
     (1) <======================>  WAN Line
		                  (1) --> PC1
		                  (2) --> PC2
		                  (3) --> PC3

Happy Browsing.