Archive for the ‘Solutions’ Category

Using iOS Devices with Wired-Only Hotel Internet

Wednesday, August 17th, 2011
I got a call from my brother saying he had searched everywhere and was unable to find instructions on how to use his iPad in his Hotel room when he goes overseas. The WiFi was too expensive, but there is a wired connection in the room that is free. It caught me off guard since all the tech people I hang out with would have know the answer instantly. For those that don’t…Take a small wireless router with you. The Apple Airport Express is small, but you can also get standard consumer brands cheaper. Simply treat the hotel Ethernet jack as the internet and plug it into the WAN/Internet port of the router. Now you have your own private wireless.

Cut Spam with SpamAssassin Rules

Tuesday, March 23rd, 2010

I don’t admit it often, but I read email headers. It’s my form of entertainment. I get, like everyone, a good amount of spam. The other day I decided to try and take an active role in blocking it. While I had always used the SpamAssassin options available through my control panel, I had never really gone deep into SpamAssassin Rules.

SpamAssassin is an open source project to assist with the filtering of spam. It runs on the server-side, and is available through many hosting plans. The popular CPanel interface has an icon dedicated to it. The examples in this post are based on the CPanel configuration, which will be enough for most users. If you are interested in more advanced configuration options, I provide a link below.

The idea is simple, while the actual function is complex. SpamAssassin examines all incoming emails and assigns scores based on a combination of header and text analysis, Bayesian filtering, DNS blocklists, and collaborative filtering databases. Each test adds to the score and the result is then used to decide if the email is spam, or not. The higher the number the more likely it is that the message is spam.

The most common settings are:

Enable/Disable: Enables or disables the filtering
Required Score: The score at which an email is considered spam
Auto Delete Enable/Disable: Enables auto-deletion of emails
Auto Delete Score: The score at which the emails will be deleted automatically
Blacklist: A list of email addresses or patterns that should always be blocked
Whitelist: A list of email addresses or patterns that should always be allowed
Rule/Test Scores: The ability to override the default scoring system

Many of these are self-explanatory, and the scoring system is interesting.

Note that, in the list above, there are three scores – Required Score, Auto Delete Score, and Rule/Test Score. The third one is the one I have come to see as very powerful, and we’ll get to that in a moment, but first lets examine the others. Both the Required Score and the Auto Delete Score default to 5. (Remember that a higher number means it is more likely to be spam). What many people don’t realize is that these two scores do not need to be the same. Before you start changing these, you need to understand that if you are too aggressive you may end up with false positives, which would mark valid emails as spam. Worse yet, you could auto delete an important email. Your clients will frown on this, so be careful. If you adjust it in small amounts, and then watch your spam folder, you can tune it over time.

I have my Required Score set at 2.7. That means any email that scores 2.7 or higher will be marked as spam. SpamAssassin then adds ***SPAM*** to the start of the subject line, and adds a flag in the email header as well. Your email client can then use the header information to filter the spam into a SPAM /Junk Mail folder. I suggest you watch those, read their headers, and learn what score those emails are getting. Are there any false positives? If so, adjust the settings as needed.

I have the Auto Delete Score set at 4. That means any email scoring 4 or higher is removed. I never see it. The result is that any email scoring 2.6 or less makes it to my inbox, 2.7 – 3.9 is flagged as SPAM, and 4.0 and higher are deleted.

These settings were actually working for a long time. Recently however, I have noticed some changes. I have seen an increase in emails that are clearly spam but not scoring high enough to be auto-deleted. These spammers, while I hate them, are getting smarter. They figured out how to beat the default, well published rules. No problem, we can change the default scoring to match their messages. First, we need to know what rules to change, and that’s where reading the headers comes in. Below is a sample email header from a recent spam email:

X-Spam-Status: Yes, score=2.9

X-Spam-Score: 29

X-Spam-Bar: ++

X-Spam-Report: Content analysis details:   (2.9 points, 2.7 required) pts rule name              description —- ———————- ————————————————– -0.0 SPF_HELO_PASS          SPF: HELO matches SPF record 0.2 HTML_IMAGE_RATIO_04    BODY: HTML has a low ratio of text to image area 0.0 HTML_MESSAGE           BODY: HTML included in message 1.7 MIME_HTML_ONLY         BODY: Message only has text/html MIME parts 1.1 HTML_MIME_NO_HTML_TAG  HTML-only message, but there is no HTML tag

X-Spam-Flag: YES

In the list of rules you will notice that each rule is preceded with the score given this email. For example:

1.1 HTML_MIME_NO_HTML_TAG  HTML-only message, but there is no HTML tag

In this case, the test name is HTML_MIME_NO_HTML_TAG and it has a default score of 1.1. Why would an HTML message not have an HTML tag? Most clients, such as Apple Mail or Outlook, would create properly written emails – we hope. So SpamAssassin gave this email 1.1 points for the error. What you need to do is identify a pattern in the spam messages you are getting.

In my case I found the rule RDNS_NONE was very common. This test checks the reverse DNS for the last untrusted relay. The default score for this rule is .1 and I was seeing this in well over 50% of my spam. I decided to change it to 2. After a week or so, I noticed that the new score was causing more spam to be caught. I was getting no false positives, and some obvious spam messages were now being flagged properly. For most,the resulting score was around 2.9. That meant the message would have had only a .9 before my change. A lot of messages were now landing in the 3.5-3.8 area. In an attempt to push those to the auto delete range, I bumped the RDNS_NONE score to 2.5 and the amount of Inbox spam fell greatly. Some was auto-deleted, and some was simply moved to the Spam / Junk Mail folder. While I still check the Spam folder for false positives, the main goal was achieved –  it was not in my Inbox.

The process for entering a test with a custom score is not obvious, so the next screen shot displays the test entered before it is applied:

It is important to note that the RDNS_NONE test is not without risk. As stated on the official site:

Note that this may be done by interpreting information in the relevant Received header – if reverse DNS checks are not performed by the first trusted relay, or if they are not recorded in the Received header, this test will be triggered (regardless of the actual rDNS status).

That means that false positives are possible, but that is why my Auto Delete Score is higher than the Required Score. While a legitimate message may get 2.5 points for this test, I am gambling it won’t get enough total points to be auto-deleted.

RDNS_NONE is just one example of possible tests, but why stop there? By customizing a well thought out list of test scores you can greatly cut down on the amount of spam in your inbox. You can find a list of  the available tests for your version of SpamAssassin, and their default scores, here.

For those that want more control, you would require access to a few configuration files. Depending on the file, changes can be site-wide or user-specific. See the documentation for more information.

iPhone & iPad Apps – A Wish List

Tuesday, March 2nd, 2010

I have had an iPhone since the day it was released. I upgraded to the 2nd generation, and eventually the 3GS, the day they were released. Why? Because they have changed the way I interact with the data and technology I access regularly. Once the App Store opened, that interaction exploded. Research shows that iPhone users use 5X more monthly data than BlackBerry users. Yes, 5X! Users now have access to a large selection of handset operating systems, but not all with the wide selection of apps available for the iPhone. Android is coming on fast and strong, and Windows Phone 7 Series based handsets will be here before you know it, but the iPhone & App Store are here now. Add the soon to be released iPad to the mix and this will be an interesting year for the mobile user.

A few months ago I started thinking about apps I wished were available for the iPhone, and then it happened. Apple announced the iPad. I am not here to debate if the iPad will succeed, while I think that it will. I know that, for my needs, it could have a place in my workflow. If I do buy an iPad, it will be because of the apps.

Below is a list of some apps I would like to see on the iPhone, iPad, or both. Some of these already exist from third parties, but I would like to see what an Apple implementation would be like.

(more…)

Fastmac’s U-Socket: USB & AC All In One Wall Plate

Thursday, February 18th, 2010

There have been more than a few times when I tried to find a USB power adaptor. I always have a cable for the iPhone, but often don’y have the power adaptor with me. Now we have the U-Socket from Fastmac. It’s a standard dual socket wall outlet, with 2 integrated USB ports! I could see adding these to any office, bedroom, or kitchen. The manufacturer’s site states:

This item is currently waiting on final UL Approval. It is scheduled to begin shipping in the first quarter of 2010.

The normal price shows as $29.95, with a pre-order price of $19.95. I am not sure it’s worth it, but the convenience would be great.

The Mother-in-law’s Switch to Mac

Monday, November 2nd, 2009

A 5 year old, home built, Windows XP machine is what started this. It was going to be fun. Yes, fun to migrate my mother-in-law, from Windows, to a new 21.5″ iMac. Her older model PC had a kid’s account on it. Yes, those little ‘people’ that are smaller than we are, but often think they are smarter. The machine had all the required protections one could think of, anti-virus, automatic updates and the use of limited accounts in XP. But, it didn’t have any anti-kid software. My fault I guess. I knew it needed it.

It would seem these guys were smart enough to ask grandma to log into an admin capable account so they could ‘do homework’. Uh, homework requires admin rights? Hum. An install of Limewire later and we end up where we are today. A reinstalled PC for the kids, and a new ‘Grandma Only’ iMac. The fun begins…

The re-install issues with the PC were crazy. I won’t go into it here, but let’s just say the fun was fading fast. It should have been declared a paperweight, but it made no sense to invest money in a machine for the kids. Underpowered or not, it could be saved, and it was. Once it was declared Kid-Safe it was time to take the PC data and move it to the Mac.

The email client on the PC was Outlook 2003. It seems there is no easy, & free, way to migrate email from Outlook (not Outlook Express) to Apple’s Mail.app. This version of Outlook uses the proprietary .pst file for all data storage. I did not like the export format choices available. There are paid apps, like Little Machines O2M which, for $10, is supposed to migrate Outlook mail and folders. The reviews I saw were mostly good ones, but it just seemed crazy to have to pay. After a lot of browsing, I settled on installing Eudora on the PC and importing the Outlook data. Then I moved the Eudora data to the iMac and imported it into Apple’s Mail.app. Worked great, except that I ended up with a ton of empty emails. It seemed like one blank email for every real email. At first I thought maybe that was how the email existed in Outlook but when I realized every sub-folder had the same issue I figured it was something to do with conversion. I actually wanted to try it again to see what would happen, but at that point I was just glad to have it done.

Contacts were not that bad. I figured the easiest way was to use a standard vCard format. Note that word ‘standard’. In Microsoft talk that mean ‘everyone but us’. Outlook does not have an export format that makes it easy, but there is a way. Select all the contacts in Outlook and under the ‘Action’ menu is a command to forward them as vCards. Genius. I can forward vCards but can’t export them. So Outlook knows what they are and by choice is screwing with me. I just mailed them to myself, saved them out and imported them into Apple’s Address Book app.

For printing, the plan was to use the existing printer, connected to the Mac as the print server. It was connected to the iMac, setup and tested. It used a Gutenprint print driver and then it was shared. Looking good. I had Bonjour installed on the PC, but could not get any printing going. The Bonjour Print Wizard would see the printer and add it, but no luck. I reinstalled Bonjour without any better result.  I tried installing the printer on the PC manually, while using a generic Postscript driver as I had seen recommended. Nope. I tried entering a network printer on XP using a queue path to the iMac’s CUPS printer. For refernce, the path is http://<IP address of Mac>:631/printers/Queue Name. No luck there. I decided to try Bonjour again and it worked. No friggin’ idea why. Nothing changed. But why question it. I ran to the next challenge.

I started moving her data from the PC via the LAN and was looking like it would take well over an hour. Instead I cancelled the copy and pulled her data drive out of the PC. I hooked it up with my cables, to the iMac, as an external drive using an adaptor, kind of like this one on Amazon. I had the data moved in less than 15 minutes.

At this point i just imported all the photos into iPhoto and all the music into iTunes. With nothing but documents left behind I put all of those into her Documents folder and life was good.

There were some issues that had no easy solution. She had a number of Microsoft Publisher files. There is no equivalent to Publisher on the Mac platform, and no way I found to easily convert the files. I say easy because I could have opened them in publisher on the PC and exported them in some common format, like HTML. But, she would still not have the Publisher  app she was familiar with. I have the files there if needed, and can always do the conversion route. Since they are all at least a year old, I figured it may be best to have her learn how to create them on the Mac, using Mac apps. Movie Maker files were also a no go. Again, I kept them just incase she ever needs them but for now the migration is done.

Since the move, she has had no major issues. The Apple Mail toolbar disappeared for some unknown reason but it was a great lesson, and easy, to show her how to bring it back. The printer paused inexplicably, and wanted admin rights to resume. I am not sure what triggered it, since I was not there, and I’m not sure why it needed admin rights to un-pause, but it was an easy fix.

Al-in-all, not too bad. She now has a fast and reliable machine. The kids? A slow and painful computing experience. I feel so bad for them.