Monday, July 20, 2009

Rose Garden at Hartford,CT

We recently had the pleasure of visiting the Elizabeth Rose Garden in Hartford,CT. Established in 1908, it is the first municipal Rose Garden in the United States. Tucked away in Hartford suburbs, is this beautiful sprawling garden located at the corner of Prospect street and Asylum street. Rose Garden being the main attraction, with lovely arches made up of climbing roses, leading to a gazebo in the center, I bet in its prime bloom, would be the perfect spot for a picturesque wedding. There are other flower gardens too along with some green houses. We reached the garden late evening and with not much daylight left, the photos do not do much justice to the actual location. One has to be there to enjoy the beauty of nature combined with great landscaping.

 

Map picture

Monday, March 23, 2009

Ubuntu Vs Fedora

Everyone has a right to their opinion, a fundamental right bestowed upon us by free democratic constitution. Being in the IT field for over 14 years, i have used a variety of Operating systems ranging from the very Basic DOS to the most current version of Windows 2007 beta.

I have been an avid fan of open-source and have always been a fundamental catalyst of change towards adoption of open-source technologies to my peers, friends and family. I have used a lot of Fedora and Ubuntu. I have implemented a lot of open-source technologies both for work and personal use. I like Ubuntu for its small distribution size both for desktop and server use.

For someone who has not tried it yet, Ubuntu is as close to user-friendly as it can get, to match Windows OS. But the scary fact that I have run into is that, it is becoming one of the unstable distributions that one can find for a Desktop OS, closely following Windows. Stability is the key reason I prefer to host my apps on Linux rather than on Windows (other than cost ;-)). All my network tools run on Linux Platform. All key network services in my network, are hosted on Linux.

Fedora on the other hand, has always been consistent with providing a reasonably stable desktop OS. Its Server version, called CENTOS (though both projects do not seem to be related at all) built to be as close as possible to the commercial REDHAT Linux versions is the most stable, free OS that I have come across. Fedora’s install set is huge compared to Ubuntu, largely due to the multitude of installation options that come with it. The basic install of Fedora can still run into couple of gigabytes. But the stability of the systems installed with Fedora is unparalled compared to Ubuntu.

Ubuntu has now stepped into the mainstream with being the only alternative choice of Operating System that comes pre-installed from desktop/laptop vendor Dell. Rumors are that, soon others will follow. Fedora is yet to see anything close to that. Ubuntu, being a Debain distribution enjoys the user-friendly nature of apt, that actually revolutionized nature of application installations on Linux as a whole. Dependency resolution has long been an issue that was not addressed effectively in REDHAT or SUSE world until APT showed up in Debian. DEBIAN by the way, was a distribution built by Ian Murdock and his wife Deb, and hence the name Debian.

Yum an equivalent of APT for REDHAT or RPM based distributions was plauged with problems in its early development stages. But now with FC9 and FC10, the number of packages available via YUM is no less than APT. Yum like wine has gotten better with age, a boon that FC users like me were waiting for. Fedora has long enjoyed faithful users, while Ubuntu on the other hand is more like the new fad, that everyone is jumping into. Don’t get me wrong, I do agree that Ubuntu is the reason, common man knows about Open-Source technologies and how useful they can be. Ubuntu has brought Linux into the mainstream. Ubuntu has been the push that Linux has been dreaming about.

I now moved all my Ubuntu boxes back to Fedora, and love being an FC geek now. I realized that I missed the geek factor in Ubuntu.

Delegate Unlock User Account in Active Directory

 

I have come across couple of admins who have fought with this problem often. They want to delegate the unlock account function to more accessible, help desk team and are unable to do so. Funny way, Microsoft team thinks, this facility though readily available in Windows, is hidden from view. There is a dat file called dssec.dat in c:\windows\system32 folder. You will also see it in your workstation if you have administrative tools installed.

image

Just open this file with a text editor viz., notepad or Notepad++ (even better), and search for a string called “lockoutTime”. Its located under the “[user]” section.

image

Change the value from “7” to “0”, save the file and exit.

Now Right-Click on the OU that you want to delegate permissions on, and select properties.

image

Click on the security tab (if you don’t see one, then you have to click select View –> Advanced Features on the menu bar)

image

Click on Advanced. click on Add user, enter the username and click on “ok”. In the Permissions Entry window select the “Properties” tab. Drop down the Apply onto list box and select “User Objects”

image

You will see two new persmissions as seen in the figure above. “Read lockoutTime” and “writelockoutTime”. Any user with these two permissions will be able to lock and unlock user accounts, in that OU.

Cheers

Most Useful Cisco IOS commands

I have to admit that I am not an avid cisco person. Just a make do, kind of person like most. Below is a list and explanation of the most useful cisco IOS commands that I have found in my general use. Please feel free to add stuff as you go:

 

1) ‘do’ command

It is a wonderful command that a nice wise guy at CISCO thought of. It was so annoying for me to constantly go back to exec mode from command mode, just to execute some exec commands viz., show.

eg: do show running-config

 

2) time-range

very useful for setting time-range for IP ACL lists. it works like aliases for time-ranges

eg:

time-range lunchbreak

periodic weekdays 1200 to 1300

 

3) show running configuration of a single interface

Another extremely useful command. Its a pain to go through the show running-config command output, specially ‘cause of the time it takes to show the config, specially on lengthy configurations. This is mostly due to the fact that it gathers all the required variables before it shows the config.

A time saver in this case is the below command:

show running config interface serial 0/0

It can also be coupled with the do command to execute the same in the config mode

do show running config interface serial 0/0

 

4) no ip domain-lookup

A very valuable time-saver command for me. I have fat fingers and often tend to typo on my IOS commands. I hate that the router takes a while and tries to resolve my command and takes forever to give me the prompt back. This is usually the first command I enter on a router.

 

5) no logging console

Are you annoyed by the constant logging of error messages on the console, that upset the continuity of your commands. Though not a problem theoretically, it is a problem when working on the console. Use the below command to get rid of that.

no logging console

Tuesday, March 27, 2007

Classless Static Routes using DHCP server

A very hidden and untalked about feature of Microsoft DHCP server is the ability to publish Classless Static Routes to DHCP clients. I have been looking for a feature like this at my company for a while now and was hitting a dry spot over the Internet. So, once I figured out how to successfully do this, I wanted to share it with anyone else who would be looking for this.

Situation:

Consider a situation (like mine), wherein you have a corporate network and want to assign static routes to your client machines, historically the but the only obvious options were:

- to use a *.cmd or *.bat file that the users could execute
- to use a Group Policy to push routes to users

None of these options appealed to me, 'cause about 30-40 percent of my users were mobile users, who often traveled around with their laptops. I did not want the static routes assigned to them, when they connect remotely. Also, they moved frequently between offices and it would create a havoc if they had those routes assigned to them when they were connected at a remote office.

The best possible option would be to somehow assign these routes via DHCP so that their mobile computers forget the route as soon as they disconnected from my network.

This is possible via DHCP option 249 and the appropriate RFC can be found at IETF. I would sincerely recommend giving the RFC a read. It isquite small and easy to understand. Windows 2003 server comes with this option, but for if you are a Network guy who is stuck with Windows 2000 Server (for whatever reason), then you can follow the steps below to
achieve the same:

- Start the DHCP Console


file:///media/sda1/Downloads/Blog/dhcpconsole.png

- Right- Click on "server options" and select "Set Predefined Options" file:///media/sda1/Downloads/Blog/setpredefoptions.png
- Click on "Add" in the "Predefined Options and Values" window, and it
will bring up the "Option type" Window.

file:///media/sda1/Downloads/Blog/addoption.png

- In the "Option Type" window type in the details as shown in the
figure below:

Name = Classless Static Routes
Data type= IP Address : check the checkbox for Array
Code= 249
Description= You can type in any description you want.

file:///media/sda1/Downloads/Blog/classless.png

- Click on "OK" and click on "OK" on the Predefined Options and Values"



Now a little theory on how this Classless Static Route works (or you
could just read the RFP noted above) :

It takes two parameters:

- Destination Descriptor
- Router/Gateway

Destination descriptors describe the IP subnet number and subnet mask
of a particular destination using a particular destination using a
compact encoding. With this kind of encoding the first octet describes
the width of the subnet mask, followed by all the other octets of
the subnet number.

eg:-





































Subnet number Subnet mask Destination descriptor
0 0 0
12.0.0.0 255.0.0.0 8.12
12.0.0.0 255.255.255.0 24.12.0.0
12.19.0.0 255.255.0.0 16.12.19
12.32.131.0 255.255.255.0 24.12.32.131
12.219.0.128 255.255.255.128 25.12.219.0.128

Now that we know how it works, lets start configuring the Scope Options.

- Right-click on "Scope Options" and select " Configure
Options". Select "249 Classless Static Routes" and add the network
address and gateway address one after the other as shown in the figures
below:



file:///media/sda1/Downloads/Blog/addstaticdone.png

- This is how it would look in the DHCP console

file:///media/sda1/Downloads/Blog/addstaticgwdhcpcon.png

- Check your DHCP client ( you may have to renew your IP address for
changes to take effect). Open Command Prompt and type in "route print"

file:///media/sda1/Downloads/Blog/routeprint.png

It sure worked for me.