Best Practice Ezine #93   Ipconfig -setclassid and other switches

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Best Practice Ezine #93  Ipconfig -setclassid and seven other switches

The purpose of this week’s ezine is three fold:

  1. To give readers another chance to download my free ezine.
  2. To thrown down three more challenges.
  3. To encourage you to apply my Litmus test idea to life in general.

Three more Challenges

My Litmus Test theory predicts that Professionals can find and configure the following ipconfig commands.  Meanwhile, amateurs will struggle to get the switches working.

1) Ipconfig check the eight switches:
all, release, renew, displaydns, flushdns, registerdns, setclassid and showclassid

Amateurs are not aware that Ipconfig has switches.  Professionals regularly select the best Ipconfig switch for the job.

You may have been using Ipconfig to troubleshoot TCP/IP since NT 4.0.  Yet you may not have noticed that Microsoft has gradually extended the range of Ipconfig switches from
Ipconfig /all  Ipconfig /release and /renew

To include a family of DNS troubleshooting switches.
Ipconfig / displaydns, flushdns and registerdns

Hardly a week goes by without -flushdns helps me to cure a connection problem.  What -flushdns does is delete stale cached information.  Bear with me if fall back on the backslash instead of the hyphen, for example ipconfig /displaydns works, but purists wrap my knuckles for not using the modern, ipconfig -displaydns.  DNS has a trilogy of Ipconfig switches, -registerdns being the final member of the trio.  Resuming my theme that Ipconfig keeps on developing new capabilities, Vista has a new switch called Ipconfig -allcompartments.

Windows Server Training

Ipconfig -setclassid

While all IT staff probably know of Ipconfig, I bet that few could name all eight switches.  For example, hardly anyone uses -setclassid.   The idea behind setclassid is to create two or three User Classes.  The point is that you can then give machines different DHCP options, for example a desktop class and a laptop class.  To give a more specific example, managers’ machines could have a default gateway to allow internet connection but other machines are confined to the company network.  What the setclassid does is tell a client (XP) machine at boot up which classid to pick up from the DHCP server.

This is a gross digression, but it is does have a relevant point.  I once knew an Irishman called Paddy.  It was winter in Ireland, and every day he went out into the wood next to his house and dug a hole, then filled it in.  It seemed truly pointless, at least to me.  When I questioned Paddy he said he dug the holes just to keep his hand in as every spring he came over to England and worked Tar-Macadaming the roads.  You see there was no work for Paddy in Ireland in the winter, and at that time his road gang only worked in the summers.  Now when it came to hiring men for the spring job in England, who do you think was the first name on the foreman’s list?  You don’t have to be a mastermind champion to work out that it was Paddy.

Now the convoluted relevance is that you could keep your skills up-to-date by setting up setclassid, actually it’s quite a challenge to configuring the DHCP end.  Who knows, you may even discover a killer use for this setclassid switch.  I have prepared detailed instructions on creating classids here.

2) Netstat -obe 

I selected Netstat -obe just because I like the acronym  -OBE (Order of the British Empire).  Seriously, with switches you often need someway of remembering obscure letter combinations.  The real meaning is, O for owner, B is the executable and E is for Ethernet stats.  Netstat is handy for gathering information for troubleshooting and -obe filters the information to a size that I can absorb with one glance.

Guy Recommends: The Free IP Address Tracker (IPAT) IP Tracker

Calculating IP Address ranges is a black art, which many network managers solve by creating custom Excel spreadsheets.  IPAT cracks this problem of allocating IP addresses in networks in two ways:

For Mr Organized there is a nifty subnet calculator, you enter the network address and the subnet mask, then IPAT works out the usable addresses and their ranges. 

For Mr Lazy IPAT discovers and then displays the IP addresses of existing computers. Download the Free IP Address Tracker

Shoe salesman.  A non-computing example of a Litmus test.

Over the last three week’s my mission has been to introduce the concept of Guy’s Litmus tests.  I expect that you have noticed that most of my examples have a serious business purpose, yet I hope you pickup on their lighter aspect of having fun while learning.  My greatest hope is that you will actively look for Litmus tests of your own.  Moreover, you can apply this Litmus test idea to every walk of life.  To finish this topic, I have distilled a recent test from a visit to a shoe shop.

Suppose you are faced with a choice between a $40 shoe, which is comfortable, but is last year’s model, or the very latest design that costs $75, has the more fashionable logos, but cramps your toes.  The amateur assistant says, ‘The $75 shoe looks really smart and your toes will soon adjust to the shoe’.  They lie, if a shoe is uncomfortable when you buy it the problem always gets worse, never better.

The professional assistant says, ‘If it is really more comfortable, choose the $40 shoe’.  They say this because the assistant knows there is a good chance you will return to their shop for more shoes.

Guy Recommends: Tools4ever’s UMRAUMRA The User Management Resource Administrator

Tired of writing scripts? The User Management Resource Administrator solution by Tools4ever offers an alternative to time-consuming manual processes.

It features 100% auto provisioning, Helpdesk Delegation, Connectors to more than 130 systems/applications, Workflow Management, Self Service and many other benefits. Click on the link for more information onUMRA.

Will and Guy’s Humour

Appropriately, this week we feature – 39 Things you should know by now


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