What would you do?

[RichB]

I have been having problems with the DFS roots around school, I started this job around 15months ago and they never have been quite right fast one day, slow another! now just generally slow, so here are my options:

 

Flatten the file servers running 2003R2, upgrade to 2008R2 reset up the DFS roots and card teaming

 

Carry on investigating the issues, as flattening the servers may not solve the issue???

 

(have to say I have tried just about everything as the why they are slow, Average disk queue smashing out at 100%, tried upgrading memory, upgrading firmware, drivers, disabling antivirus, checked DNS, DHCP, card teaming, running through one 1gb card, new namespaces, re-config of some areas of DFS) but as I’m sure your all aware DFS is a mine field in itself.

 

What would you do? And why?

[glennda]

what raid cards do you have in the server/s?

[RichB]

RAID cards? or network cards?

 

Its RAID 5 with broadcom netextreme 2 cards and intel pro 1000 quad port on the teaming cards

[glennda]

Raid cards

 

What model server is it? If you have high disk queues i'd be looking there, also why type of disks you got in it?

[User3204]

What are you putting on the DFS roots ?

 

When this was all new technolgy, I read somewhere that you only want to put stuff onto it that gets changed infrequently, but needs to be acccessed a lot.

So good for netlogon, apps shares, shared desktops / startmenus

Bad for user shares.

 

It may have gotten better since then.

If you run Wireshark on a server when it is running slowly, you should be able to see what the traffic is doing.

 

 

I made sure that no-one apart from the ICT techs can write files to them.

[RichB]

already ran wireshark, everything looks correct!

 

DFS roots were designed for file shares ect! Or from what I have read and seen in other schools/universitys.

 

The DFS roots hold everything, shared areas, userdata, profiles ect.... Had no problems what so ever till a recent upgrade on our DC's to server 2008.

 

got a dell poweredge 2950, 15k disks

[User3204]

Faulty switch(es) on your server core then ?

 

Any DFS root must be pushing through a lot of network traffic, I DON'T use them, apart for read-only stuff, as if f'r example

 

user logs into \\domain\users\%username%

it attaches them to the server \\server1\dfsusers\%username% any AND all changes to this will have to be replicated to all the other servers on the root \\domain\users\ so the files will be copied to:

\\server2\dfsusers\%username%

\\server3\dfsusers\%username%

\\server4\dfsusers\%username%

 

or however many servers you have.

[pete]

Thou shalt toddle off to Ask the Directory Services Team blog and read:

 

O DFS Where art thou? Part 01

O DFS Where art thou? Part 02

O DFS Where art thou? Part 03

 

It's seriously worth it - reading that blog on a regular basis has helped me a lot. Lots of articles on DFS.

 

Also - are you mixing FQDN and Netbios names in DFS? That'll get you into a world of slowness and delays. Pick one and stick to it throughout.

Edited October 19, 2011 by pete