Author: 1

enable SELinux and a reboot can take forever

misc

Adding more machines for INTERDUBS. They get tested, triaged and configured for a ridiculous long time. That way once they are production machines they do only one thing: Run.

We experimented with benchmarking the performance effects of SELinux. As we expected it is not worth disabling. But now we know. We also know something we should have known: Enabling SELinux again on a bigger file system will make the next reboot take forever. Hours. Of course it makes sense, since all files will have to be relabeled.

vans and the places they have been in

art photo

A very nice project

A small vertical slice of (Socal) life. Marvelously documented while it is fading out of existence.

cool IP, hm, maybe not so

history internet

As we are running slowly out of IP addresses addresses are being used that were deemed to be reserved. This wouldn’t be the internet if this would go smooth. See pollutions in 1/8 for the details (thanks David for the hint).

Turns that out that 1.1.1.1 and 1.2.3.4 and not so awesome choices for an IP. Others thought so before.

forecasts

economy history politics

And they keep doing them:
Very nice visualization by the times

getting shells in the same path

Command Line linux technology

Often I work with a couple of shells simultaneously in the same directory. One may be the editor with a program in it, and the other one running it.
When I add the following lines to .bashrc


alias sd='pwd > /tmp/ddd'
alias d='cd `cat /tmp/ddd`; pwd'

I just need to type ‘sd’ (for Set Directory) in a shell that is already in the right directory. When I then log in with the other shell a simple ‘d’ gets me where the other shell already is. Extra benefit: When I want to continue where I was last I just type ‘d’ again. Just a little thing. But the world is made out of little things. Lots and lots of them.

osx wrtg54 connection reset ssh

linux OSX

When using via the wrtg54 ssh connections timed out after a while.
Which is was mildly annoying. The problem that with mildly annoying things is they are mildly annoying.
So one does not go and fix them soon enough. In this case it was terribly easy to cure errors like:


Read from remote host 1.2.3.4: Connection reset by peer
Connection to 1.2.3.4 closed.

All that it needed was to create a file called .ssh/config in the home directory and add something like these lines:

ServerAliveInterval 60
ServerAliveCountMax 5000

Nice that it didn’t require any changes on the other end.

gmail backup

google linux

Over the last years I accumulated quiet a bit of mail in Gmail. It works, and I find it very inspiring to see its features grow while I keep all my data. But I also grew worried: What would happen if my mail should go away? I have paid google exactly zero for keeping all my email. There would be nothing I could do.

Turns out that it is possible to make a copy. Googles own Matt Cutts described it well

I found that these getmail parameters worked well for me:


[retriever]
type = SimpleIMAPSSLRetriever
server = imap.gmail.com
username = EMAIL@gmail.com
password = PASSWORD
mailboxes = ("[Gmail]/All Mail",)

[destination]
user = getmail
type = Maildir
path = /root/.getmail/

[options]
read_all = false
verbose = 2
received = true
delivered_to = true
message_log = /root/.getmail/gmail.log

It took a while. Actually days. It seems that you only get mail out at a slow data rate. Then there is a bandwidth limit. getmail failed after a while with:


getmailOperationError error (IMAP error ([ALERT] Account exceeded bandwidth limits. (Failure)))

Just waiting a couple of hours took care of this. Having had the mail not backed up for 5 years it was quiet alright to wait 5 hours.

Another error occured with 5 mails. Getmail for instance would end with:


getmailOperationError error (IMAP error (command FETCH ('3049', '(RFC822)') returned NO))

And it would do so repeatedly with the same number. I assumed that something had gone awry with those mails. After pretending that the mail already had been retrieved via the oldmail-imap file getmail soldiered on.

Tragically at some point my connection went away. I had downloaded around 120,000 mails during that session.
Getmail updates the oldmail-imap file only when done (or cancelled via ctrl-C). So the next time it started I went to download the same mails again.

Even with that glitch things worked out. And I feel pretty good about having a copy of my mail now.

Having a secure copy of your data is never a bad idea.

Only 99 decades left till 3000

history misc

thank you sqlite

technology

Since more than 25 years I write computer programs. Writing some information to a file for later use is a very common thing. It worked (most of the time). But it never felt right. Common up with a format, creating a writer and a parser. All that can be done. Rather mundane. Finally I switched to using sqlite for this kind of thing. And this feel right. It works. And will just cover 99% of all cases were I have used “fopen” in the past. One of the things that I like about coding for a living is that it keeps getting better. Not me, that’s for sure, but the tools. And that almost makes up for the natural decline in raw brain power.

corporate video

internet technology

Remember the look of corporate Videos?

Well, things change.

I found this video for Cooper Union on The C47.

In the right hands you can make some very compelling images with a camera body that retails around 2.700 $US.

I had hopes that miniDV would spawn new content, due to the leap in quality of the recording technology. It didn’t work out that way.
I am hoping again that the 5D Mark II and similar devices do that.

At least wedding videos will look better than they used to.