XenServer Mailer Obscurity
I’m a very big fan of Citrix products, XenServer in particular, but some things just leave me scratching my head.
The mail services in XenServer is one of them. For such a complex piece of software, the mailing process is vague and obscure. We ran into a problem where the syntax used by XenServer was causing the XenCenter e-mail alerts to fail, and we could not receive vital e-mail messages from XenCenter. You can check your logs in your XenServer’s console here:
/var/log/maillog
When you find messages like
Jan 21 03:47:39 {HOSTNAME} sSMTP[21838]: 501 Syntax error in address noreply@{HOSTNAME}
you know you’re in trouble.
Normally, this would send you off to modify the sSMTP conf file like this
nano /etc/ssmtp/ssmtp.conf
but your modifications will get you nowhere. It isn’t until you read the source code for Xen located at https://github.com/xen-org/xen-api/blob/master/scripts/mail-alarm that you understand what’s going on. The relevant section is:
# mail-alarm: uses ssmtp to send a mail message, to pool:other_config:mail-destination
# If /etc/mail-alarm.conf exists then it is used as the ssmtp config.
# However, this script first replaces any macros with keys from pool:other-config.
# For example, if /etc/mail-alarm.conf contains the text @MYMACRO@ then it will
# be replaced by pool:other-config:ssmtp-mymacro# If /etc/mail-alarm.conf exists then it is used as the ssmtp config.# However, this script first replaces any macros with keys from pool:other-config.# For example, if /etc/mail-alarm.conf contains the text @MYMACRO@ then it will# be replaced by pool:other-config:ssmtp-mymacro
So in actual fact what you need to do is to simply copy the changes you made to /etc/ssmtp/ssmtp.conf to a new file in /etc called /etc/mail-alarm.conf:
cp /etc/ssmtp/ssmtp.conf /etc/mail-alarm.conf
A simple enough procedure, but good luck finding much mention of it.
Mac Keyboard Issues with CoRD
From time-to-time you come across problems with Microsoft’s Remote Desktop Client for Mac (for example the dreaded “…cannot verify the identity of the computer to which you want to connect” message).
A fantastic alternative to Microsoft’s RDP client is CoRD, a Simple RDP Remote Desktop. The most recent version as of this writing is 0.5.5 and can be found on SourceForge.
If you need to have multiple Remote Desktop windows open, CoRD is a must.
The problem however can sometimes be incorrect keyboard mapping. The solution is a simple one, but may not be obvious. If you live in Canada for example and have your keyboard set to the Canadian keyboard, you will often find that your keyboard mapping is incorrect when logging in (press | and get <). That causes all sorts of problems, for passwords especially. Worse yet, switching applications will often necessitate another Alt-Shift to get back to the proper keyboard mapping.
If you’re suffering from keyboard mapping issues, simply close CoRD and then use finder and go to the Applications folder. Right click on CoRD and select “Show Package Contents”. Navigate to Contents –> Resources and open “windows_keymap_table.txt”.
The solution for Canadian keyboard issues was simply to replace (or invert – your choice) the entry next to Canadian. By default, you see:
Canadian=0×1009
Replace it with the US code 0×409:
Canadian=0×409
Save the file, and relaunch CoRD.
Farewell, Steve
Such an exceptional person.
Many meticulously detailed people can produce fantastic works in small quantities, others forgo detail in favour of large volume and are masters of production. He was one of the rarest of people who could not only do both, but extended the boundaries of what was technically possible with every new product he oversaw. That such quality and attention to detail, such care and craftsmanship, could be found in affordable, mass-produced products was something special.
RIP Steve Jobs, I loved being amazed.
Remote Control Worms With Laser Light, Using FOSS
All I can say is “WOW!” (from Slashdot as usual):
“…to share a new tool I’ve developed for neuroscience that uses optogenetics to remotely control the neurons of a worm as it swims or crawls. Its called CoLBeRT, Controlling Locomotion and Behavior in Real Time. With the instrument I can induce the worm to stop, accelerate, lay eggs or experience the illusion of touch. All source code to run the instrument is GPLd and available. Science News and Scientific American both have stories. The project homepage is at colbert.physics.harvard.edu.”
Site Creates Profiles From Public Records
Taking the origins of Facebook one step further…privacy issues are finally publicly ramping up…
“Online dating company Gotham Dating Partners has announced plans to create profiles for non-registered individuals based on publicly available information from social networking sites, e-mail registries, mailing lists, marketing surveys, government census records, real estate listings and business websites. Although the Australian Privacy Commissioner has warned that the automatic creation of identifiable profiles of individuals without their knowledge is ‘not good privacy practice,’ Gotham Dating Partners does not expect to face any privacy issues from the move, which is expected to boost its membership from 6.5 million to 340 million worldwide.”
Facebook Opens Up Home Addresses and Phone Numbers
These types of notices are becoming far too frequent:
“Do you really want third-party app developers on Facebook to be able to access your mobile phone number and home address? Facebook has announced that developers of Facebook apps can now gather the personal contact information from their users. Security firm Sophos describes it as ‘a move that could herald a new level of danger for Facebook users’ and advises users to remove their home address and phone numbers from the network immediately.”
Spam Volume Spikes After Holiday Respite
From Slashdot:
“The amount of spam hitting users’ inboxes fell off a cliff in late December, with many security experts attributing the decline to the sudden disappearance of the Rustock botnet and other networks from the spam business. But the level of spam has begun to gain back some of the ground it lost today as other spammers have taken up the slack. Researchers say that after the sudden drop-off in spam volumes, things stayed fairly quiet for a time, but now it seems that other spammers have picked up where Rustock and the other spamming operations left off. The volume of spam took a big jump upward in the last 24 hours, according to researchers at Websense. The volume of spam hasn’t made it all the way back to the levels of the last few months of 2010, but it seems to be on the way.”
Apple’s Cloud to Boot Future OS
From Slashdot:
“Apple has received a patent that hints at the intent of providing network computers that will boot through a ‘net-booted environment.’ It may seem that Apple is moving slowly into the cloud computing age and that it has many assets that are simply not leveraged in what could be a massive cloud environment that could cause more than just a headache for Google and Microsoft. However, it appears that Apple has been working for some time on an operating system, conceivably a version of a next-generation Mac OS or iOS, that could boot computers and other devices via an Internet connection.”
Software Longevity
I’m amazed to constantly be working on software these days for which much of the code I wrote 10 years ago. I honestly never expected the code I wrote to be in use for so many years…
Slashdot: How To Be Popular On Facebook, Quantified
Interesting Facebook data mining results:
“Network World reports that Facebook has just released an analysis of the word usage for about one million status updates from its US English speakers with the words in updates organized into 68 different word categories based on the Linguistic Inquiry and Word Count (LIWC)–a text analysis software program that calculates the degree to which people use different categories of words across a wide array of texts. The results? To be popular on Facebook all you have to do is write longer status updates, talk about music and sports, don’t be overly emotional, don’t talk about your family, don’t refer to time and use the word ‘you’ a lot. Facebook’s study also confirms something that bloggers and Fox News have known for years: negative comments produce more online activity. Sure,
Facebook users might click the like button more often on updates expressing positive emotion. But Facebook found you can’t beat negativity for user engagement, as dismal status updates garnered more comments than positive ones.”
MacBook Air USB Network Port
Although it’s advertised as nothing more than a 10/100 network port, I’m shocked at how much slower traffic passes through it. Definitely much slower than 100 Mbps was on my MacBook Pro’s internal port.
I need to get some metrics on this thing…
MacBook Air vs. iPad
This week’s lesson:
MacBook Air + Roger’s Rocket Stick > iPad + 3G
MacBook Air
Playing around with my new 13″ MacBook Air. Very impressed so far. Same speed (if not better) than my 15″ MacBook Pro and so much lighter and more pleasant to work with.
Missing the back lit keyboard, but you adapt fairly quickly. I can’t believe they packed so much technology into such a small package.
Truly amazing.
Microsoft Windows 8
So it looks like Microsoft Windows 8 will be released in October of 2012.
Gartner Thinks Android’s The Winner
Gartner believes that Android will overtake all other smartphone operating systems by 2014 assuming we all survive past 2012.
It is generally considered unwise to go against Gartner predictions. I really like my iPad and my Blackberry, but looks like I’ll have to give Android a try now…

