Tomasz Korwel
programmer, administrator, engineer – my everyday fights with reality

Note: Newer version of the procedure is here

I use it all the time. I’m taking it everywhere with me together with my laptop. Thanks to it’s wirelessness it’s easy and nice to handle. I like this mouse a lot. The only problem I have encounter is dirty roll. It slowly stops working – first in down direction. if you press it a little bit dipper it still works, but only for a moment. Then other directions stop working too. Apple’s provided method of cleaning usually works only for couple of minutes.

So out of desperation I started to look for methods to disassemble it. Unfortunately Apple decided to glue it together so you can’t disassemble it without breaking things. Although some say you can glue it back I don’t like this solution at all.

Some googling later I think I have found the solution. If Apple’s cleaning method doesn’t work for you anymore proceed to second step. Find a flat surface and lay a sheet of white printer paper on it. Then turn your mouse upside down and, for about 1-2 minutes, do this:

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After some time you should start seeing small dirt leaving your mouse and staying on the paper. Don’t expect too much – there isn’t much space inside the mouse for dirt to accumulate, yet it’s enough to prevent it from working. Anyway judging from amount of dirt my mouse left on paper it should work like new – and in fact it does!

Technorati Tags: wireless, mouse, Apple, cleaning, working

I’ve just received a phone call from a guy who claimed he is FBI agent. He said that my email server has been compromised over a year ago and used in crime activity. Then he started to ask some very detailed questions (like if it’s company server, if this server is used in government related activity, what type of software is on the server). Despite I’m quite knowledgeable person regarding my servers and I’d rather notice it being compromised, detailed nature of those question made me suspicious.

Why would he ask such detailed questions over the phone? And why is he asking about informations he could easily get by himself just from using Google and web browser? There is more – he reached me under the number which is not listed anywhere in connection with my domain – so he apparently didn’t even used whois service.

Considering all that I asked him why does he need all those informations? He replied that he’s trying to build a case and he wants to check if I was a victim (my server was compromised and used in some illegal activity without my knowledge) or if I was taking active part in this activity. Wait a minute – since when FBI agents call you in advance telling you that they are thinking about building case against you? So I kindly replied to him that I’d be more then glad to give him all those information in person as it’s apparently a big case. And here even bigger surprise was waiting for me – he said that Iowa is to far away from him and he hung up.

Unfortunately I didn’t have a chance to get his name or town from which he’s calling. Whole call lasted less than 2 minutes and my thinking in English is still to slow to quickly react. But I suspect that all those questions were leading to some identity theft attempt.

The only thing that’s bugging me – how did he get this phone number?

Technorati Tags: phone call, FBI, agent, identity theft

New boy arrived yesterday:

And this is how my work place looks now:

Yes, the second one (double monitored) works under XP, and it’s not going to change anytime soon. Thanks to Synergy I’m controlling MacBook using same keyboard and mouse I use with windows desktop – it speeds my work quite a bit.

Technorati Tags: Synergy, MacBook

Today suddenly my email server stopped accepting incoming connections. I wasn’t able to send any emails. After careful checking logs I have figured out that I’m a victim of DOS attack. More – I asked for it tuning maximum number of incoming connections in my firewall to low. Anyway, after correcting firewall I started to look over the internet how to better secure my Postfix configuration to prevent such problems in the future. What I have found is some simple main.cf tweaks posted on the nixCraft site:

disable_vrfy_command = yes
smtpd_delay_reject = yes
smtpd_helo_required = yes
smtpd_helo_restrictions = permit_mynetworks,
reject_non_fqdn_hostname,
reject_invalid_hostname,
permit

smtpd_recipient_restrictions =
permit_sasl_authenticated,
reject_invalid_hostname,
reject_non_fqdn_hostname,
reject_non_fqdn_sender,
reject_non_fqdn_recipient,
reject_unknown_sender_domain,
reject_unknown_recipient_domain,
permit_mynetworks,
reject_rbl_client list.dsbl.org,
reject_rbl_client sbl.spamhaus.org,
reject_rbl_client cbl.abuseat.org,
reject_rbl_client dul.dnsbl.sorbs.net,
permit

smtpd_error_sleep_time = 1s
smtpd_soft_error_limit = 10
smtpd_hard_error_limit = 20

Simple as that, and it works. Now I can see how my server is rejecting spammers one by one without even talking to them past HELO command.

Technorati Tags: email server, DOS attack, Postfix

I have just upgraded Firefox to it’s newest version. Of course there was problem with extensions – some of them are still not compatible with the newer Firefox. One which I needed the most for everyday work is the Zend Studio Toolbar. But I have found this blog so quick modification and test and voila – I have my toolbox upgraded. Time to go back to work…

Technorati Tags: Firefox, Zend Studio Toolbar