Weekly spam summary on January 27th, 2007

This week, we:

  • got 14,755 messages from 268 different IP addresses.
  • handled 23,910 sessions from 1,483 different IP addresses.
  • received 248,718 connections from at least 75,622 different IPaddresses.
  • hit a highwater of 37 connections being checked at once.

Volume seems noticeably up compared to last week . The apparent jump in the number of differentIP addresses trying to talk to us concerns me,


Why DWiki doesn't use fully REST-ful URLs

REST is a style of web application writing where, among other things, youuse simple structured URLs to represent resources instead of heavilyparameterized ones. For example, 'https://example.com/users/cks/' is aRESTful URL but 'https://example.com/users?name=cks' is not.

(RESTful URLs are virtuous for a number of reasons, including being lessalarming to search engines and being simpler, so it's easier for peopleto remember them


Why I think that DNS whitelists are going to fail

There's been a recent fad for DNS whitelists, the rough inverse of DNSblacklists; instead of listing claimed bad sources of email, they listclaimed good sources. I've been thinking about this for a while, and Ibelieve that such DNS whitelists are going to fail.

Why I believe DNS whitelists are doomed can be summed up in a simplequestion: do you whitelist Hotmail or not? If you whitelist Hotmail, youare whitelisting a known source of a not insignificant amount of spam.If you


First impressions of pyOpenSSL

pyOpenSSL is a high-level Pythonwrapper around a subset of the OpenSSL library (to quote it). It waspulled onto my machines recently as part of a Fedora update, and sinceI'm currently interested in OpenSSL-related things I decided to playaround with it to try it out.

After writing some basic stuff, I have to say that I like it. It's notentirely documented (and for some things you really want to read theOpenSSL manpages too), but it works fine


A clever trick to deal with students powering off workstations

One of the eternal curses of student Unix labs is students casuallyturning off workstations the way they turn off other PCs when they'redone with them. (A problem made worse by vendors putting glowing powerbuttons on the front panel of machines, where they become an easytemptation.)

In theory the answer to this is Wake-on-LAN. You probably have at leastone inaccessible computer per lab, so run a daemon on that that noticeswhen workstations are down and sends out a WoL packet to get


An irritation with current GUI interfaces

Why are programs so convinced that I have horizontal real estate to givethem? Everything seems to want to put important information in sidebarsand panels and so on (usually non-optional ones).

I don't know about other people, but for me horizontal screen space ismore precious than vertical screen space. If you eat vertical space allthat happens is that I get fewer lines of your real content (which isstill irritating; please don't). But if you eat horizontal content, yourapplication


How to stop DiskSuite resyncing a mirror on Solaris 8

One of our irritations with DiskSuite has been that it has no way toabort a mirror resync short of forcing drive errors, something thatwe actually had to resort to once and which is not always possible,for example when your drives are logical LUNs on FibreChannel RAIDcontrollers.

As we found out recently, fortunately not quite the hard way, it turnsout that there actually is a way to abort a mirror resync. If yourresyncing mirror is in a diskset, running ' metaset -s -r


Why host authentication has to check who the certificate belongs to

When using host SSL certificate to authenticate a host's identity, youcan't just check that your CA signed the host's certificate; you alsohave to check that the certificate belongs to the host (usually bychecking that the certificate's CN is the hostname, or IP address, oretc).The reason you need to make this additional check of the certificate isthat without it, you don't know if the certificate actually came fromthe host you're trying to authenticate.


Sometimes system administration requires a hacksaw

I have to admit that the hacksaw was kind of a special situation.

Our hacksaw usage came about when we were pulling an old rack from ourmachine room to make space for a new and better rack. The old rackhad a bottom plate that was just a frame, with a big opening in thecenter, and long ago we'd routed the power cord for the rack's powerdistribution unit (PDU) through that opening (presumably to keep thingsneat) instead of just out the back.

Normally


Weekly spam summary on January 20th, 2007

Our SMTP frontend crashed a lot this week, so the connection volumenumber is a lot more approximated than usual. Having said that, thisweek we:

  • got 14,060 messages from 292 different IP addresses.
  • handled 21,260 sessions from 1,496 different IP addresses.
  • received over 183,239 connections; I'm not going to try to guessat the minimum number of different IP addresses.
  • probably hit a highwater of 6 connections