onsdag 29 oktober 2008

windows command of the day

you can pipe stdout to the clipboard in windows.

example:
ipconfig /all | clip

lördag 25 oktober 2008

google reader keyboard shortcuts

speaking to a unix-consultant at work yesterday, he told me that I had to use the old vi keyboard shortcuts to navigate in a console menusystem.
i told him that it was no problem and that i have owned oreilly's learning the vi editor for eight years.

but then i struck me.
i use the google reader shortcuts a lot and the shortcuts for "up" and "down" is the same as for vi!

"k" for up and "j" for down.

fredag 17 oktober 2008

windows command of the day

this is a old one. but sometimes you scratch your head trying to remember this one:

subst:
Associates a path with a drive letter.


kind of an old shool symoblic link for windows.

lets say for example that you remove a computer from the domain for a retired user that has a lot of files linked to his old home directory. and you have copied over all the files from the network drive to a folder on the local harddrive. and you just want to get it over with and have some well deserved coffee.

use subst and walk away :).
i have plans of writing down som guides on how to deploy windows with MDT both to macs (bootcamp) and the asus eeepc. over wireless.

stay in tune.

in love with resource monitor in server 2008



sitting home on a friday night a bit drunk and monitoring the migration from our old mac-based fileserver at home to the new windows-based one. installing WSUS 3.0 SP1, Windows Deployment Toolkit and running robocopy. listening to old school electronic music and sipping on a beer.
at last some sunshine after a hard week at work.

onsdag 8 oktober 2008

dynamic DNS clients is not registering when using non Microsoft DHCP-server

scenario:
the clients are getting their DHCP-leases from a non-microsoft server and is using the DNS-server in server 2003 as DNS.

problem:
no clients are updating their A RR:s in DNS.


accordning to Microsoft, with the default settings, all versions of windows from 2000 and up should register their own A records and ask the DHCP-server to update the corresponding PTR-records.




but in my case, this didn't happen. i verified that it wasnt a permissions error by setting a static IP and saw that the records got registered.


today after tearing my hairs out for months i finally figured out that the "ask the DHCP-server to register"-part is the culprit.



from this draft http://tools.ietf.org/html/draft-ietf-dhc-dhcp-dns-12:
"If a client that owns/maintains its own FQDN wants to be responsible for updating the FQDN to IP address mapping for the FQDN and address(es) used by the client, then the client MUST include the Client FQDN option in the DHCPREQUEST message originated by the client. A DHCP client MAY choose to include the Client FQDN option in its DISCOVER messages as well as its REQUEST messages. The rightmost ("S") bit in the Flags field in the option MUST be set to 0.

the client sets the 0x00 flags and wants to register its own A-records:


okey, i knew that. but why is it not updating?


then i found this:
"Even, if the Client FQDN option carried in the DHCPREQUEST message has its Flags field set to 0 (indicating that the client wants to update the A RR), the server MAY (under configuration control) update the A RR. The update MUST be originated following the procedures described in Section 5.4. The server MAY originate the update before the server sends the DHCPACK message to the client. In this case the RCODE from the update [RFC2136] MUST be carried to the client in the RCODE2 field of the Client FQDN option in the DHCPACK message, and the Flags field in the Client FQND option MUST be set to 3."

the server replies back with the flags 0x03 which tells the client NOT to update its records, because the server will do this for him.



so XP and Vista is following the RFC-draft but the DHCP-server (who has the ability to register the RR's) tells the client not to do it!



aah, the satisfaction of solving a hard problem. can't beat it :)