Procurve Best Practices: auto-negotiation and fiber optics

First off, let me say that fiber optic connections using Procurve equipment do not auto-negotiate.

And yet, there is a setting to set your mini-GBIC (SFP) to 100-half, 100-full, 1000-half, 1000-full, and even auto-1000.

This is retarded. Fiber by it’s very nature is ONLY full-duplex; one strand for transmit, one for receive.

This being said I feel like you should NEVER set your fiber to anything other than ‘auto’. Sure, you can set both ends to 1000-full and it will work just fine…… what of what benefit is it? I’ve taken snapshots of interface stats, and compared between connections that are hard set to 1000-full, vs. those simply set to ‘auto’. There was NO difference whatsoever; and this was not over just a few days or weeks, but months. So then of what benefit is setting your interfaces to 1000-full? None, in my opinion. It’s just a few more lines of code that have to maintained. The KISS principle should be applied in all possible areas.

Oh and BTW, if one end of your fiber is set to 1000-full and the other to auto, you will NOT get a link.  I can’t tell you of how many new installs this has bitten me.

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Posted in Best Practices, HOWTO's, Procurve | Leave a comment

HOWTO: Reinstall iManager 2.5, Apache2, and salvage iPrint

Your certificates need to already be in order for this to actually work.

I’ve had iManager 2.5 blown up on my iPrint server for a few weeks now, which means I haven’t been able to do any administration of my printers. That’s bad.  I tried to do an inplace upgrade to iManager 2.6, but that did nothing for me. I determined that the problem was somewhere within Apache, and ended up uninstalling Apache2, Tomcat, and iManager.

Oops.

iPrint itself is now broken. In my haste I didn’t stop to think that it actually relies on Apache for all of my printing, via the IPP URL….. so when I blew away Apache, I broke printing totally…… what now?

Time for lunch.

After eating a sub, I realized that my fix was an easy one; just reload iManager, Apache, and Tomcat off of the CD through the GUI, and it should re-write my config files. I can handle that. So I do this, and to my joy, iManager is back in business. However, printing through IPP is still not working. I check my Apache log screen, and see that it is not listening on port 631 like it should be. Now, I go digging through my httpd.conf, comparing it to my old version (yes, the backup saved my can today) and compared. They are basically identical except for one line at the bottom:

include iprint/ipp.conf

So I added this in, restarted, and everything is back online.

Now, it’s officially a ‘good day’. 🙂

Posted in HOWTO's, iPrint, Netware, Novell | Leave a comment

HOWTO: Delete local users through Group Policy and vbscript

If you deal with imaging a lot, you’ve probably run into a situation where you have some local users on a workstation that you don’t want to be there, maybe they were creating during the OS install or whatever. It’s also handy if you are moving someone to a domain setup, and need to get rid of their old local accounts to prevent them from logging in as the local user instead of the newly created domain user.

You need only paste the following into a plain text file, and rename the extension to .vbs:

strComputer = “.”
strUser = “user”
Set objComputer = GetObject(“WinNT://” & strComputer & “”)
objComputer.Delete “user”, strUser

Next, create a new GPO, add .vbs this as a startup script under Computer Settings, associate with an existing OU containing you domain computers.

Posted in HOWTO's, Microsoft, VBScript | Leave a comment

Google is taking over!

Ha.

Well I’ll say this: I’ve decided to start using google documents instead of sticking with my Hamachi solution that I mentioned earlier. I came to find that at certain sites my Hamachi performance was quite inconsistent, especially if I was tunneling through port 80, which I am in most cases. Upgrading to the ‘Premium’ version helped somewhat, but it was still a pain. I’ll stick with it for lan gaming over the net, but not much else at this point.

So now I use gmail for all of my email and now google documents for storing my stuff.  I was already using google for all of my research. Google is good. Google FTW.

Posted in Cool Stuff, Random Bits, Tech / IT | Leave a comment

HOWTO: Import and Export DHCP reservations in server 2003

Load-balancing your DHCP has been well documented, but the matter of synchronizing your IP reservations has always the fly in the ointment. But no more.

To export DHCP reservations, from the source server:

netsh dhcp server [ip address] scope [scope address] dump>reserv.txt

Open up ‘reserv.txt’ in a text editor, do a Find->Replace for the source server IP, change to the destination server IP. Trim out everything in the file except for the reservations themselves.

On the destination server, make sure your scope is already created, and run the following command:

netsh exec C:\reserv.txt

Tada. The only problem is that as your add more and more reservations, you’ll need to add them to each server that you are load balancing. It’s easier to do that than to do another export.

Posted in HOWTO's, Microsoft | 37 Comments

Virtual Servers with VMWare

I installed my first production virtual server host over a year ago using a product called ESX Server by VMWare. Simply put, it is awesome! I have had four moderate use file servers running off of this virtual server, for about 1500 users in all running on this with abosolutely no problems. The virtual machines were Windows Server 2003, and I kid you not, only one server out of the bunch had to be rebooted in a years time. That is what I call low-maintenance and reliable!

ESX Server is an impressive peice of software. The host machine basically runs a razor-thin vesion of linux tuned for running virtual machines, and it gives each VM direct access to hardware, which translates into near-standalone performance, given the other VM are not hogging those same resources at that given moment. I’m running this current setup using a Dell PE2850, 2-way dual-core Xeon chips, and 8 gigs of RAM. Performance has NOT been an issue at all. I’ve just installed a new ESX server this week, also running 4 VMs, but this server has 2-quad core Xeons and 16 gigs of RAM. I was tempted to see how well this machine would run Supreme Commander, but you know……. I don’t get paid for that 🙂

VMWare Server, the free version, is also a very worthy program. If you are not buying all of the addons that are available for ESX Server such as VMotion and VirtualCenter (which I *HIGHLY* recommend you do!), then VMWare Server and ESX Server are very comparable in terms of features. The main difference of course, is that VMWare Server uses Windows Server as it’s host OS, and performance-wise it can’t hold a candle to ESX. I’ve been using Server in several locations now in production for hosting web servers, log server, and light duty file servers, with absolutely no problems.

Posted in Cool Stuff, VMWare | 1 Comment

HOWTO: Create an ISO in linux with DD

During my second install of ESX Server, I decided that I needed speed up the deployment of my Server 2003 virtual machines. The last time I setup ESX Server, which was over a year ago, I simply created an ISO on my laptop and set it as the virtual CD-drive. It was pretty fast, but it would obviously be faster if the ISO was actually sitting on the server itself. No big deal, the Virtual Infrastructure Client supports this. You just have to login to the server console as root or equivalent and use the DD command. For Server 2003, I did:

from within /vmimages,

dd -if=/dev/cdrom of=w2kstd_r2_1.iso

Pretty elemental stuff I guess, but I doesn’t hurt to document.

The install SCREAMS!

Posted in HOWTO's, Linux | 2 Comments