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Oct 06 2009
VMware Virtual NIC Choice and SYSPREPing Templates Print E-mail
Written by Paul Winkeler   
Tuesday, 06 October 2009
Under ESX 3.5 an enhanced NIC choice called vmxnet became available but only to 64-bit VMs. The idea behind this new virtual device is that by publishing itself as TCP/IP offload capable, the Windows OS will not bother to encapsulate data into a TCP/IP packet before handing it to the ethernet driver, instead leaving that task to the (virtual) hardware. As a result, the vmxnet device no longer has to parse and strip the TCP/IP packet information so it can hand the payload off to the *real* physical NIC and everybody wins.

This improvement was big enough that numerous VMs have been changed to 64-bit even if the guest Windows OS was still 32-bit; all just to gain access to that more efficient NIC. But guess what? No good deed goes unpunished and indeed neither does this one. When one of my customers came to me a few weeks ago with a scenario that prevented her from SYSPREPing a VM she tried to create from a template even after installing every SYSPREP CAB's contents into all possible folders, we, as well as VMware support, were stumped. Finally we discovered that the reason the option to customize the template deployment was grayed out was because of the mismatch between a 64-bit VM and a 32-bit guest OS! All we had to do was convert the template to a 32-bit VM and everything worked as advertised.

My biggest gripe here is that the VMware GUI gave absolutely no feedback to this effect. None. Zero, Zip, Zilch. Ah well, live and learn.

Last Updated ( Tuesday, 06 October 2009 )
Sep 09 2009
IAX2: A bit more official Print E-mail
Voice Security and Privacy
Written by Administrator   
Wednesday, 09 September 2009

After many years of hard work the Inter Asterisk eXchange protocol version 2 (IAX2) has been published under the auspices of the IETF as RFC 5456. Note that the editor uses the second sentence to clearly define this document: "It does not specify an Internet standard of any kind." Then again, it took the SIP RFC a long time to get to the standards track as well.

Mar 18 2009
The Six Dumbest Ideas in Computer Security and How Apple Computer Side Stepped at Least One of Them Print E-mail
Enforcement and Awareness
Written by Paul Winkeler   
Wednesday, 18 March 2009

Some of you may have heard of Marcus Ranum, a top flight security guy currently working at Tenable Security, developers/underwriters of Nessus amongst other tools. Recently someone forwarded me a link to a web-page Marcus wrote a few years ago called The Six Dumbest Ideas in Computer Security. I invite you to take a moment and read it now before proceeding on to my comments on how his observations apply to Apple Computer's iPhone platform.

Last Updated ( Wednesday, 18 March 2009 )
Feb 26 2009
Barracuda Monitoring Print E-mail
Infrastructure and Application Monitoring
Written by Paul Winkeler   
Thursday, 26 February 2009

Barracuda Neworks makes a fine line of inbound (and outbound?!) SPAM filters deployed in-line with your email server and the outside world. These devices provide a web interface both for management and configuration as well as for end-users to trawl through suspect quarantined e-mail searching for treasure. You can see how the device is performing under its current load right from the front page of this built-in website and then it can also send scheduled e-mail messages with various statistical reports. Unfortunately, what it does not do, is alert you of odd behavior in any meaningful pro-active way. After all, who has time to read through all those daily statistics reports from all their devices?!

The obvious answer to this problem then is to monitor the device through our facorite Open Source monitoring platform, Zenoss but that is where we run into a glitch. It turns out that Barracudas cannot be probed with SNMP, the standard way such devices are probed until you get to the 400-series and even then, the exposed MIB is not an enterprise specific one with Barracuda goodies but just the generic OS one, courtesy of the underlying Linux engine. Ah, you say, but doesn't Barracuda make a REST-based API available? Well yes, they do, but now we're writing a command based datasource and even then, this feature is not available until the 400-series and up.

Read on to learn how PBnJ Solutions built a Zenoss ZenPack to monitor Barracudas from the 200-series on up, now allowing everyone to not only get an alarm when the inbound queue is overflowing but also collect some great SPAM statistics over time.

Last Updated ( Sunday, 01 March 2009 )
Feb 26 2008
Military Grade Communications Print E-mail
Written by Administrator   
Tuesday, 26 February 2008
Having long been a proponent of Jabber this announcement on TMC Net is too interesting to ignore. The article even mentions SIP/SIMPLE which is the technology that bridges the Voice over IP (VoIP) and Instant Messaging worlds. For example, the current crop of Grandstream phones supports SIP/SIMPLE so text messages can be delivered directly to the phone.

But wait, it gets more interesting, Jabber has an open architecture now embodied in the form of Internet standards such as XMPP (RFC 3920 and RFC 3921), the very standards and code base upon which Google built its GoogleTalk! As a matter of fact, you can reach the author on via Google Talk because PBnJ Solutions' Jabber server is federated with Google's servers.

The question remains then, does this make me an official of the Military Industrial Complex? I think not, but it does mean that PBnJ Solutions is familiar with, and can help you implement, military grade solutions to your business problems. Need a VoIP solution? Call us and we can help get your Asterisk server up and running; IM us and we'll move you off that myriad of adware riddled instant messaging services that turn your firewall into a swiss-cheese to a rock-solid Jabber server. We'll be glad to communicate with you in any way you'd like.

Last Updated ( Tuesday, 26 February 2008 )
Feb 19 2008
Grandstream Custom Ringtones Print E-mail
Phone Tricks
Written by Paul Winkeler   
Tuesday, 19 February 2008
Most of the postings on how to get a Grandstream GXP 2000 to sound a custom ringtone when connected to an Asterisk PBX only get half the story right. This brief article attempts to set the record straight. Three pieces must fall into place:
  • Ringtone sound files
    These files must be called ring1.bin, ring2.bin and ring3.bin respectively and must be downloaded to the phone. This typically entails placing them into the /tftpboot folder on your TFTP server alongside the configuration files for the phones.
  • Phone Parameters
    Phones associate each of the three ringtones with a specific caller-id value. These caller-id values are controlled with parameters P105; P106 and P107 respectively. Pick appropriate caller-id values for each of the ringtones and move to the final step:
  • Asterisk Dial Plan
    In the appropriate place in the Asterisk dialplan then, insert a line as follows:
    exten => s,n,SIPAddHeader(Alert-Info:\;info=Special)
    Where "Special" corresponds to the parameter value you chose to associate with the ringtone you want to use for that call.
And that is all there is to it.
Last Updated ( Tuesday, 26 February 2008 )
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