Archive for the 'Techno-Babble' Category

Missing an Email? It may be Media Temple’s Fault

Published
by
Chris Meller
on November 11, 2007
in Announcements, Commentary, Hosting, Internet, Media Temple, Networking, Security, Techno-Babble and Wordpress
. 7 Comments

It started last week when I was trying to sign up for Ron Paul Christmas. For some peculiar reason, I didn’t receive the welcome email. After talking with the site owner, it turned out (mt) was rejecting the email because the email address wordpress@ronpaulchristmas.com didn’t exist on the sending server.

Now, this isn’t particularly unusual. There is no requirement1 that an email address actually exist for a server to send email as if it were from that address. This is especially true from Wordpress blogs, which often send email from wordpress@domain.com accounts on behalf of their owners. Now, since this is only used for outgoing email, in most cases users would never bother setting the email account up. Why would you? You’re never going to be receiving email there2, so what’s the point?

Well, (mt) apparently knows better than you do… For “security reasons”3, their grid service does a “callback” check on every incoming email address. If the server handling mail for domain.com doesn’t recognize that account (such as our wordpress@domain.com example), (mt)’s server will reject the message.

I’ve tried to point out that this kind of behavior can be detrimental, particularly in the age of blogging and web services we now exist in, but the best answer I’ve been able to get out of (mt) is that I should add the sending address to their Mail Protect whitelist. Well great, unless I can add *@* to the whitelist, or at the very least wordpress@*, that’s hardly a viable solution - how do I know the address that’s sending to me if I never get the email?

If you use Media Temple’s grid service4, please contact (mt) immediately and tell them this is an unacceptable situation. I love a lot of aspects of their grid service, but this is clearly not one of them…

  1. In most cases, anyway. [back]
  2. Except for bounces, should someone put in an invalid email address [back]
  3. According to the support representative that responded to my ticket. [back]
  4. Or you want people who do use it to actually receive emails you send to them. [back]

Plesk Backup Error: Specified file is not accessible

Published
by
Chris Meller
on October 8, 2007
in Advice, Daily Grind, Hosting, Internet and Techno-Babble
. 20 Comments

After upgrading my Plesk install past 8.1.1, I encountered a problem with the builtin backup utility. When attempting to create a new backup (either locally or to an FTP repository), I would almost instantly be handed back the error:

Unable to create backup session: Specified file is not accessible

I googled around and found a couple of results, including a support forum that actually had the answer to my problem burried back on the second page.

For whatever reason, Plesk loses the ability to write to its temporary directory, where all backups are held until they are completed (even for FTP destinations). I was easily able to solve this problem by (as root):

chown -R psaadm:psaadm /var/lib/psa/dumps

Note that the original author of the suggestion I used said to chmod 777 the files, but this proved to be unnecessary. I saw that the parent directory was owned by psaadm, and it just made sense that the dumps directory would need to be as well.

In any case, it worked for me. Hope this helps someone…

Interesting IP Registry Statistics

Published
by
Chris Meller
on August 23, 2007
in Cool, Internet, Links, Networking, Techno-Babble and Uncategorized
. 1 Comment

Found a cool post in my RSS feeds this morning: IP Registry Statistics

Stephen (who, by the way, lives in Boston, the lucky shmuck…) has setup a script that aggregates all the IP WHOIS data from the various IANA-designated organizations and runs some interesting statistics on them. Since I’m a statistics addict, I had to pose a few questions and observations. My response got far too lengthy for a simple comment, so here we go…

Since all their member countries are listed individually, why does the European Union have so many IPs? Wouldn’t the EU only represent actual government-used addresses?

That must be one hell of a database with 2.5 billion IP address records in it… I take it it’s running on MySQL? I’d love to see some automated processing, possibly spitting out aggregate numbers for historical reports (imagine the pretty IPs -> IP Exhaustion graphs).

I find it interesting that, according to Wikipedia, industry experts expect us to run out of IPv4 addresses sometime between March and May in the year 2010; but that here we are in August of 2007 and we’ve only used 2,534,086,476 of the available 4,294,967,2961 public IP addresses.

Talk about an exponential increase in usage. In the entire history of IP-based computing, we’ve used (about) half of the IPs, but in less than 3 years we’re going to use the other half? Just out of curiosity, I had to do some math.

Do you realize that, assuming we meet their expectations of running out of the remaining 1,760,880,820 IPs by March, 2010 (about 950 days away), that means we’re allocating a net of 1,853,558 additional IPs a day? That’s almost 2 million IPs a day…

That’s 1,287 IPs every minute, 21.5 IPs per second.

Somehow this seems unreasonable to me… But then, I guess I’m not an industry expert, huh?

  1. Per the above Wikipedia entry. This doesn’t exclude private subnets or multicast addresses, so my later figures aren’t going to be entirely accurate - just mostly. [back]

The Interesting 700MHz Spectrum Auction Rules

Published
by
Chris Meller
on August 16, 2007
in Commentary, Internet, Links, Networking and Techno-Babble
. 0 Comments

This story from Ars Technica, about the pending 700 MHz wireless spectrum auction (via Digg here) really interests me.

Just when I think the FCC can’t be any more generally useless and that, unless Google grabs up the entire spectrum, we’ll further be doomed to more Ma Bell / AT&T anti-competitive practices in the US wireless market, something amazing happens.

Not only have the FCC adopted two open access policies for the national spectrum (requiring open devices and open applications for all customers), which had been heavily advocated by Google to help open up the market, even if a single company were to snag the entire spectrum; but the FCC have also carved out several portions of the spectrum that would be reserved for local / regional use only.

This really is amazingly good news if you think about it. Say we have a worst-case scenario: AT&T drops a huge chunk of change to snag up the entire national spectrum in the auction. Well that’s alright, because smaller organizations can still bid on the regional portions of the spectrum and continue to offer competitive services to a more focused market. Simply because they don’t have the bankroll of a mega corporation, doesn’t mean they’re completely out of the market.

On top of everything else, there are built-in requirements for these areas of the spectrum that govern how much of the licensed region must be provided service within x years.

Finally, the smaller portion of the national spectrum comes with an added bonus… and an added curse… for the company that purchases it. They get a small chunk of wireless spectrum for their own evil purposes, but they also get a significantly larger chunk for free. One caveat: they have to build out a public services network on this extended real estate. That means they’ll have significantly higher implementation costs to develop the actual network, but after it’s in place, they get free use of this additional spectrum (provided it’s not in use for the public services at the time). In the end, everyone really wins, as long as a company can find it financially reasonable to take this jump.

I don’t know about everyone else, but I’m looking forward to these auctions next year. This should be a pretty exciting time for wireless technology, regardless of who wins the national chunk in the end.

OS Upgrades Coming down the Tubes

Published
by
Chris Meller
on August 7, 2007
in Announcements and Techno-Babble
. 3 Comments

Just a little warning that tomorrow my blog will likely be intermittently unavailable while I’m performing a couple of OS upgrades which will require at least two reboots (that I know of).

I hate rebooting a live server, it always saddens me to see a quality uptime disappear just like that…

22:32:39 up 97 days, 14 min, 3 users, load average: 0.03, 0.06, 0.01