How To Sync Twitter To Google+
Ever since Google+ came out, I’ve been looking for a way to automatically sync my twitter updates to it. Yeah, yeah, I know the API has been released to developers but the tools I use on a daily basis (most notably hootsuite) don’t have integrated support yet.
So after some lengthy testing/googling, I FINALLY came across a method for doing it. The only problem? The steps were a little convoluted. For that reason, I thought I’d re-write them and hopefully make it a little easier for the next person who tries this.
Examining Load Average
It’s nearly six years old but this article is still one of the best written explanations for how load averages work.
Highlights:
The load averages differ from CPU percentage in two significant ways: 1) load averages measure the trend in CPU utilization not only an instantaneous snapshot, as does percentage, and 2) load averages include all demand for the CPU not only how much was active at the time of measurement.
Authors tend to overuse analogies and sometimes run the risk of either insulting the reader’s intelligence or oversimplifying the topic to the point of losing important details. However, freeway traffic patterns are a perfect analogy for this topic, because this model encapsulates the essence of resource contention and is also the chosen metaphor by many authors of queuing theory books. Not surprisingly, CPU contention is a queuing theory problem, and the concepts of arrival rates, Poisson theory and service rates all apply. A four-processor machine can be visualized as a four-lane freeway. Each lane provides the path on which instructions can execute. A vehicle can represent those instructions. Additionally, there are vehicles on the entrance lanes ready to travel down the freeway, and the four lanes either are ready to accommodate that demand or they’re not. If all freeway lanes are jammed, the cars entering have to wait for an opening. If we now apply the CPU percentage and CPU load-average measurements to this situation, percentage examines the relative amount of time each vehicle was found occupying a freeway lane, which inherently ignores the pent-up demand for the freeway—that is, the cars lined up on the entrances. So, for example, vehicle license XYZ 123 was found on the freeway 30% of the sampling time. Vehicle license ABC 987 was found on the freeway 14% of the time. That gives a picture of how each vehicle is utilizing the freeway, but it does not indicate demand for the freeway.
Moreover, the percentage of time these vehicles are found on the freeway tells us nothing about the overall traffic pattern except, perhaps, that they are taking longer to get to their destination than they would like. Thus, we probably would suspect some sort of a jam, but the CPU percentage would not tell us for sure. The load averages, on the other hand, would.
Use netcat to check udp port status
Damn you, Windows. You’ve conditioned me to use telnet for network connectivity checks instead of superior tools like netcat (which supports UDP ports).
I nearly forgot this one so I thought I’d write it down:
nc -vzu <ip address> <udp port or port range>
- -v enables verbose mode for easier feedback.
- -z scans for listening daemons without sending any data to them.
- -u uses UDP instead of TCP.
‘Nuff said.
A Day (Almost) Without Technology
As regular readers of my blog may or may not recall, one of my resolutions for the new year is to find ways to disconnect from technology on a regular basis. Today, my wife and I decided to try this and the results were intriguing.
Here’s a GREAT summary of Protect-IP and how it threatens the Internet as we know it. Please watch and share.
Note to Hollywood: multiple monitors does not a supercomputer make.
Reason #126845267 why I love my job: signs like this.
Today’s youth guess what 80’s and 90’s technology does.
I’m noticing a startling similarity between the UI on some Web 2.0 sites and toddler DVDs. Hmmm.
Ahh good ol’ technology.
Random thought of the day: Am I the only one who thinks of Back To The Future 2 when hearing about Kinect + Skype?
How to install CA-signed TLS certificates in Sendmail
I thought I’d document the setup process for Sendmail using CA-signed certs. Why? Because most certificate authorities will require intermediate certs and additional steps are required; steps that aren’t easily available online for some reason.
I should also point out that TLS will usually work fine with self-signed certs. This procedure is for environments that, for whatever reason, MUST use CA-signed certs.
Simple Explanation of SMTP Error Codes.
I usually don’t like anything from about.com. Every now and then I’ll get flashbacks from when they had that AWFUL toolbar that got added to external links on their site (yuck). That being said, I do have to give Heinz Tschabitscher props for providing a succinct and clear explanation of SMTP errors. While geeks like myself enjoy RFCs, it can be intimidating for email newbies (or just damn boring).
Shh. You had me at CONNECTED(00000004)…
I’ve been absorbed into the wonderful world of SSL recently (particularly certificate chain validation) and thought I’d pass along a few helpful commands:
openssl verify -purpose sslserver -CAfile <ca bundle> <cert file>
This helps check if a signed cert matches with a cert bundle (including all intermediates and root). It’s useful since some certificate authorities can require different intermediates and have somewhat misleading instructions on which to use (I’m looking at you, Network Solutions).
openssl s_client -CApath <root truststore directory> -connect <recipient web server>:443 -showcerts
This command string is useful for examining standard SSL connection information and validating the provided certificates against a trustStore directory (containing root certificates).
openssl s_client -cert tls-cert.pem -starttls smtp -connect <recipient mail server>:25
This command string is a slight variation of the one above it. It’s useful for troubleshooting TLS-related issues as they pertain to SMTP. In addition to providing information on the certificates being exchanged, it will submit the STARTTLS command as part of the connection attempt and allow admins to continue a manual SMTP session through a TLS encrypted tunnel.
Hot damn! Someone actually tried upgrading through (nearly) every major version of Windows. I’ve been wondering what this would look like.
