Archive for February, 2009

Windows XP: Automatic Updates

When reviewing Windows XP Eventlogs I encountered the following two error messages.

Event Type: Error
Event Source: ESENT
Event Category: (3)
Event ID: 453
Date: 2/11/2009
Time: 1:39:16 PM
User: N/A
Computer: IVAN-VM-01
Description: wuaueng.dll (3172) SUS20ClientDataStore: Database C:\WINDOWS\SoftwareDistribution\DataStore\DataStore.edb requires logfiles 678-682 in order to recover successfully. Recovery could only locate logfiles up to 681.

Event Type: Error
Event Source: ESENT
Event Category: (3)
Event ID: 454
Date: 2/11/2009
Time: VM1
User: N/A
Computer: IVAN-VM-01
Description: wuauclt (3460) Database recovery/restore failed with unexpected error -543.

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The client also did not receive any Updates since those started. It seems that for whatevet reason the SoftwareDistribution database used by “Automatic Updates” service was corrupt. To fix this problem:

  • Go to Services.msc and stop “Automatic Updates” service
  • Go to C:\Windows and rename/delete folder C:\WINDOWS\SoftwareDistribution\
  • Start “Automatic Updates” service

Immediately after this action was done the client downloaded the patches from the WSUS server.

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Windows Active Directory:dc vm

If your domain controller is not receiving any updates from it’s replication partners and you see a lot of error messages and warnings in the Eventlog than you are lost! It happened to me last couple weeks and for days I tried to figure out why this domain controller was not working. I had the vm on my usb disk and run it on several pc’s. The domain controller was running on a Windows Server 2008 OS.

EventID 1925, 1435 and 1663 warnings were showing up in the Directory Services events. After restarting the "Active Directory Domain Services" services and rebooting the vm for couple of times I was not able to fix the replication. I even reset the computer account password with netdom.exe and still no success.

At some point I started troubleshooting and run dcdiag.exe. Dumped the output to a text file and went through and I saw some bad news…

Starting test: Replications
   REPLICATION-RECEIVED LATENCY WARNING
   NET-DC-03:  Current time is 2009-02-08 17:01:25.
      DC=ForestDnsZones,DC=Networknet,DC=nl
         Last replication received from LABN-MSX-01 at
    2008-10-26 15:22:49
         WARNING:  This latency is over the Tombstone Lifetime of 60  days!

If you ever receive the "This latency is over the Tombstone Lifetime of 60" warning on a domain controller than there is no other work around than seize the FSMO roles to antoher funtioning dc and force the dcpromo.exe removal from the system. After the server has been rebooted run meta cleanup of the obsolete records.

Related links:

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Riverbed: 6months review in enterprise network

Today I received the following email from Riverbed in my mailbox:

Cost savings, data protection, and productivity remain top priorities driving major new IT initiatives. As organisations look to accelerate applications, consolidate infrastructure and optimise bandwidth utilisation, they are increasingly turning to WAN optimisation providers like Riverbed to help them face these challenges for their data centre, branch office and mobile worker environments.
Join Steelhead Mobile Product Marketing Manager Joe Ghory to hear the latest developments on Steelhead Appliances and Steelhead Mobile. Attend this live webinar to find out how you can:
• Run applications up to 100x faster over the WAN
• Consolidate infrastructure without compromising performance
• Optimise bandwidth
• Achieve extreme cost savings

For some time I have been thinking writing a post on this topic and my experience from a engineering and design perspective. Reading this email I wanted to share some information.

Pros:

  • Save costs with smaller links (less bandwidth is needed)
  • Office backup solutions (only bits which have been changed during that day will be copied)
  • Branch office senario when working with limited amount of documents in global teams. Working with one 5mb file on central file server from China, India and US together performs very well.
  • Centralized Web servers in the datacenter and SPS works good as documents will be optimized
  • Mobile client for remote users is very good.
  • Disaster recovery when using DFS links 
  • VMWare Server 2.0 to run VMs (RiOS 5.5)

Cons: 

  • CIFS traffic is not optimized if content is jpg, avi or other multimedia type. Riverbed can’t optimize this and thefore most bits are being copied over the WAN. Working with remote file server this is really a problem if no local share is available for such content.
  • CIFS traffic is not optimized if you are searching for files on a remote share. I have seen various examples finance people are searching for an important file which is stored in a 4GB folder. CIFS traffic is than not optimazed and utilization of the network link is high.
  • Encrypted traffic like HTTPS in not optimazid. You could import SSL certificates for intranets and have HTTPS optimized, but donwloading drivers with Lenovo System Updater won’t work and all bits are being copied. This becomes issue if there is no QoS rule when the network link is full and users are using remote file share.
  • Several document types are not performing well; I have seen access databases; excel, project and autocad files not performing very well with optimization from Riverbed.  Some are bug related, but imagine 25MB excel file with diffrent links to other files. Having centralised file server with riverbed optimilization still forced us the have local file share with access databases.
  • File sharing and Print services are not performing very well when enabled on the appliance. It uses Samba server for file sharing and saw permissions issues. With CUPS print service it also did not perform when having 50 users connected to the appliance due to high CPU load. Mabye already fixed now. With release 5.5 a vm with Windows Print Server can be installed.

 

I believe Riverbed is promising technology for business environments spread all over the world. Microsoft is improving their protocols for file sharing, Riverbed is enhancing their RiOS and the solution is suitable for all environments. I think you should evaluate the solution and think about what you want to achive in the end.

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