Tuesday, June 23, 2009

A good new blocklist

Something new to report to my readers! I found a good new DNS blocklist today, called Brracuda Reputation Block List. Here is the relevant info:

Website: http://barracudacentral.org/rbl

DNSBL domain: b.barracudacentral.org
Uses A type records
Reverse IP address for lookups
Supports DNS TXT records

Result IP is

Number of hits is much higher than my other two popular choices, Spamcop and Spamhaus. Will let you guys know if I have any issues with it.

Wednesday, June 10, 2009

Backup MX records

I learned something today. Backup MX records can be a bad idea from a spam standpoint. Apparently, spammers have figured out that servers higher up on the MX priority chain do not have as much spam protection, but rather just generally collect everything and dump it to the primary server. So by sending spam directly to the backup servers, spammers can bypass blocklists and some other methods of filtering.

Thursday, June 4, 2009

Car handsfree bluetooth

I really do enjoy the built-in bluetooth hands-free system in my car that allows me to talk on the phone through the sound system. However, I have noticed one unusual tendency of mine.

I am in the habit of switching though radio channels via the little button on the steering wheel. I have noticed that when my girlfriend calls and starts yelling at me for some reason (does she need a reason?), I find myself hitting this button to try to change the channel. Alas, to no avail. Every channel is her.

Wednesday, June 3, 2009

Offline files recovery

Holy moly. For the first time in many years, I have found myself inadvertently breaking the golden rule of IT work. I did not leave myself a way back, or at least for about 30 scary minutes I thought I had not.

What happened is a client had a machine connected to a defunct Windows domain. This domain had not existed in a few years because the domain controller was long broken down. However, the client continued to log into her domain account, and, more critically, had continued to save all of her critical files to a network drive letter tagged for offline caching.

Not thinking anyone would do this, I mindlessly just joined her machine to a new domain. And of course things went downhill from there, when she told me where her files really were. Naturally, I could not log back into her other profile to recover those files, because that domain was forever gone.

As she was about to start crying, I frantically searched for a solution. Thoughts of copying the old profile to the new one came to mind, and I was about to do that (maybe that was a good solution, don't know), but then I stumbled onto the real answer I was looking for.

Offline cached files are stored under %systemroot%\CSC. I checked there, and it was full of things, so I figured that was a good thing.

There is a tool called csccmd.exe which will restore whatever is in that folder to an alternate location. So for example, you will want to create a folder called c:\restored. Then run the csccmd.exe with the following arguments:

csccmd /extract /target:C:\restored /recurse

(the /recurse argument puts things in all the right subfolders)

csccmd.exe is part of Windows 2003 resource toolkit:

Hope this helps someone.

Thursday, May 14, 2009

VMware issue

Ever had an issue where the guest OS has trouble copying files from the host OS? It will start, and then cut out.

Check the event viewer on the host. If you see bunch of Denial-of-Service warnings/errors, then you have found your problem. You need to turn off DOS on the host as follows. Now I am sure some would say that you are opening yourself up to some security problem, but I always trade security for convenience, so here is what you do.

1. Launch regedit, and navigate to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanManServer\Parameters

2. Create a new DWORD Value called DisableDos, and set its value to 1.

3. Maybe reboot to make sure.

Exchange 2007 message size limits

Not as simple as it used to be in Exchange 2003. Have to set it at the transport level and also at the send and receive connector level. To set to, for example, 50MB, need to do the following:

Set-TransportConfig -MaxReceiveSize 50MB
Set-TransportConfig -MaxSendSize 50MB
Set-ReceiveConnector -Identity (connector name) -MaxMessageSize 50MB
Set-SendConnector -Identity (connector name) -MaxMessageSize 50MB

Wednesday, May 13, 2009

Older Speedstream DSL modems

I learned today that older Speedstream modems, like the one pictured, a 5100 model, do not give you an IP address, which would otherwise allow you to configure them. As far as I know, they do not have a web console. And they will not do PPPoE for you, either. If you have a router, you need to configure it for PPPoE. If you do not, you have to create a new network connection, and follow the prompts for creating a PPPoE one.