Sunday 31 January 2010

HP 1505n and Windows Server 2003 R2

I had a problem getting this printer to work a few months ago and after recently explaining this to someone else with the same issue I've decided to make a post about it here. If you download the HP LaserJet Hostbased Plug and Play Basic Driver or the HP LaserJet Full Feature Software and Driver from the HP website and use it to install the printer everything appears to work fine but then after a few prints it stopped working. In typical HP driver fashion it also sometimes takes the print spooler with it!

I've only seen this happen on Windows 2003 Terminal Servers so I'm not sure if the cause of the problem is when a Standard User tries to print. After looking at it for a while I decided to try the HP LaserJet PCL5 Basic Driver listed below which appeared to cure the problem. Hopefully if anyone has the same problem then this post may save them. This driver shows with the following name:


Regards

Monday 18 January 2010

Windows 2003 Terminal Server doesn't decrement Per User license count

This had me going for a while so thought I'd post about it here. I was asked to add some more licenses to one of our Terminal Services and decided to check Terminal Services Licensing Manager (licmgr) to double check the current license situation. There are 5 terminal services Per User licenses but I noticed that the number issued was 0.

At the time there were 5 users connected so I decided to make another connection and I was allowed to exceed the number of licenses! I didn't think this was possible and it wasn't anything I'd really paid attention to. However after looking over at Microsoft's support site I found this:

Currently, Windows Server 2003 does not manage User CALs. This means that even though there is a User CAL in the license server database, the User CAL will not be decremented when it is used. This does not remove administrators from End User License Agreement (EULA) requirements to have a valid terminal server (TS) CAL for each user. Failure to have a User CAL for each user, if Device CALs are not being used, is a violation of the EULA.

It appears this is by design, which is something to be aware of if you're expecting Windows to alert you about any license shortfalls.

Wednesday 13 January 2010

Emails arriving delayed or not at all and a Netgear Router

I had a strange problem at work yesterday that took me a good few hours to solve and I'm posting it here to try and potentially help others. We receive ALOT of spam and have a dedicated ADSL line to cope with the volume. Every now and again we receive an email where the sent time is an hour or two before it arrives in a users inbox. I'd never thought anything of it and just assumed it got caught up in the myriad of spam.

However, more recently the time differences have got larger and some emails have not arrived at all, causing some of our customers to get slightly alarmed after receiving a bounce back from us! I decided to bury my head into the problem and try and find a cause. After scouring the mail server (CentOS 5 + Kerio Mailserver) and checking the bandwidth usage, nothing really seemed to be at stretching point. I could sometimes reproduce the problem by merely telnetting to the server on port 25, where I would get an initial response but then the connection would just hang. Control + C was not successful in releasing the connection! After doing this and running tcpdump on the mail server I could see that I was never actually hitting the mail server, therefore it must be the router!

After a 5km jog I had a flash of inspiration, the router is a Netgear DG834G, which runs a mini version of Linux. A quick Google revealed you can enable telnet by browsing to the router with the following URL http://RouterIP/setup.cgi?todo=debug. After logging in you should see a web page with Enable Debug.

I then telnetted to the router (no user or password required) and checked /proc/sys/net/ipv4/netfilter/ip_conntrack_max as I knew this can be limiting factor. It was set to 2048. I then looked at the live ip_conntrack in /proc/net and could see it was full of UDP connections to OpenDNS. The ip_conntrack was getting full of UDP connections from all the DNS lookups to Spamcop etc. I was now full of hope so decided to lower ip_conntrack_udp_timeout from 60 to 10 and raise ip_conntrack_max to 4096

echo 4096 > /proc/sys/net/ipv4/netfilter/ip_conntrack_max

echo 10 > /proc/sys/net/ipv4/netfilter/ip_conntrack_udp_timeout


I checked the Kerio Mailserver which was still resolving properly and so decided to leave it at that for the following day. A full day has passed and all mail seems to be arriving as normal and we have received no more complaints. Hopefully this will solve the problem and if anything else arises from this I will post an update.

Over a month has passed and we have been problem free. This was definitely one of the more rewarding fixes!
Regards

Monday 11 January 2010

Symbol / Motorola LS2208 keyboard wedge barcode scanner issues

I had the pleasure of installing 5 Symbol / Motorola LS2208 keyboard wedge scanners. It was a job that I was expecting to take under an hour and the first three where installed in about 20 minutes and I was feeling confident it would all be over soon!

The final two scanners, where being installed in a different department and I strolled confidently into the room. I connected up a scanner, configured it using the provided configuration sheet and rebooted the PC. After a reboot neither the mouse or keyboard were working, which left me slightly perplexed considering how quickly I had installed the previous three. Nevermind, I'll try the other one. Exactly the same. After trying numerous configurations, checking BIOS settings and cables I had wasted about 40 minutes and was still confused.

I noticed both keyboards were identical so decided to try a spare one I had, rebooted the PC and it worked! From what I can gather some keyboards must not provide enough power, or for some other reason do not like being plugged in via a keyboard wedge. Either way it's another bit of information confined to the memory banks.

Regards

Sunday 10 January 2010

Iomega REV Drives format from the command line in Windows

Iomega REV drives are supposed to be a replacement for tape and we have installed many of these in servers we have deployed. From my experience they seem to be really unreliable and if we are not swapping drives out we are implementing workarounds for sporadic backup failures.

The backup success rate appears to be dramatically improved by formatting the REV drive before a scheduled bakup. This can either be done via a scheduled task or in the pre backup command for the backup software that is used.

First of all you need the Rev System Software which can be downloaded fom here.

Secondly run the following from a command prompt or a batch file:

"C:\Program Files\Iomega\REV System Software\ImDrvCLI.exe" /Drive=E: /Format

Obviously replace the drive letter with one that corresponds to your particular setup.

Regards

Server 2008 TS Licensing Diagnosis has not discovered any license servers

I came across an interesting problem a few months ago with a Terminal Server I was configuring. After installing the necessary roles via Server Manager and activating my Terminal Server licenses I noticed that TS Licensing Diagnosis said it could not discover any license servers.

Naturally I googled the problem and couldn't find anything of any use, so, for the first time I decided to phone Microsoft. Now, Microsoft's support were exceptional but after approximately 8 hours on the phone we were still no closer to finding a solution! Microsoft did say something interesting regarding the server manufacturers installation media which got me thinking that maybe it was a manufacturer specific problem. The server was a Fujistu TX200 S4 so I decided to do a fresh install with an original Windows Server 2008 installation DVD.

After going through the same procedure, voila, TS Licensing Diagnosis was correctly discovering my license server! I now knew it was something specific to Fujitsu's install DVD. I opened add/remove programs and decided to uninstall Serverview_Agents, went back to TS Licensing Diagnosis and the server could now discover the license server!

Apparently this is a Microsoft bug and KB977686 has been assigned but we are still awaiting a patch. More information can be found in the following threads, both of which I started:

Technet

Fujitsu

UPDATE:

Finally Microsft have released a hotfix for this problem, which I have installed and tested successfully.

http://support.microsoft.com/kb/977686