Writing NTFS on Mac OSX

Scored myself a new external hard drive which was pre-formated in NTFS. Thought it would be a good idea to have a drive that's in NTFS.

To write to a NTFS drive on my Mac OSX I did the following:

Installed MacFuse-2.0.3,2.dmg (outdated, successor is FUSE)
Instaled older versoin of ntfs-3g-2010.10.2-macosx.dmg (once again older version but is more stable).

Cisco Network Diagrams for Visio

I needed to update some documentation today and needed some updated Visio stencils for updated Cisco products.

Looks like the updates can be found here:

http://www.cisco.com/en/US/products/hw/prod_cat_visios.html

Cisco Global Internet Speed Test (GIST) for your mobile device

The Cisco Global Internet Speed Test (GIST) app is a free and simply app that you can use to test your network network (3G, wifi). It will provide you with the speed in kbps and catergorises the typical connection type it can handle. You can then use it to compare previous results or results compared to other locations. Good thing is that its available for your iPhone, Blackberry or Android device.

Note: you'll need to turn on location services for the app.

More details can be found there: http://ciscovni.com/gist/index.html

Although the simple test is quite handy, seems like the charts and graphics don't always appear correctly and takes some time.

Using Screen as a terminal emulator

I've been using ZTerm and various terminal emulation software on the Mac for a while.
Most have been a bit clunky, so I've reverted back to screen.
Came across an issue with it not connecting properly using my Keyspan USB to Serial adapter.
When I run the command:

 screen /dev/tty.USA19Hfa14P1.1

I get the following error:

  Cannot open line 'dev/tty.USA19Hfa14P1.1' for R/W. Resource busy.
  Sorry, could not find a PTY.

After some digging around turns out that when I last used screen, I didn't exit out of it properly.
Out of doing a: ps -f

  ps -f

  UID   PID  PPID   C     STIME TTY           TIME CMD
  501   666     1   0   0:00.00 tty.KeySerial1   0:00.00 SCREEN /dev/tty.USA19Hfa14P1.1
  501   670   669   0   0:00.01 ttys000    0:00.02 -bash

I killed the process:

 kill 666

Tried to use screen again and it worked this time around.
This is a reminder, more to myself, that you should always exit screen using the CONTROL-A followed by the CONTROL-\.

Error: ssh_exchange_identification.

Was helping a colleague with an issue today, he was reconfiguring the ip address and dhcp scope of an old Cisco PIX515E. When we tried to ssh to the PIX we got the following error:

ssh_exchange_identification: Connection closed by remote host

At first we suspected an issue with  ~/.ssh/known_hosts file. (on Solaris).  Removing the entry for the PIX in the known_hosts file and even removing the file itself did not fix the issue.

Or if you are using some Linux distribution under, /etc/hosts.allow and /etc/hosts.deny.
We checked these and this didn't resolve the issue.

Recalled having a similar issue around a year ago and it was to do with the RSA key on the PIX itself.
If you do the following on the PIX:

show ca mypubkey rsa

This will display the rsa key. We found that there was only one key that was a, General Purpose Key.
There should be one listed as an Encryption Key.

To correct this we did the following:

ca zeroize rsa
ca generate rsa key 1024
ca save all

The "ca zeorize rsa" deletes all RSA keys generated on the PIX.
We then used the second command to generate a new RSA key with size of 1024 and then saved the configuration.

Attempted to ssh to the PIX and bingo!

Tip: Grep for non-matching lines

I've been working on a lot of .config files lately and I've found the following grep command very handy.

grep -v -E '^\#|^$' test.conf

Basicaly returning all lines that don't begin with  # (comments) and blank lines. It's a quick way to see whats configured in the conf file.

The -v is the invert match, to show non-matching lines.
The -E is for extended regular expression.
The ^\# regex of line beginning with #
The | regex for OR
The ^$ representing empty lines
And of course the file you which to perform the search on.

WifiKill - Kick users off the wireless network

Was playing around with my Android phone and came across this app called WiFiKill.
It's a simple app that allows you to "kick" users off wireless network that you are in. You'll need to root your android device before you can install the app, as it needs root access.

Details and download can be found on their project page, same guy(s) that do faceniff:

 http://forum.ponury.net/

I tried this at home and it worked like a charm. Clean user interface and easy to use. Simply select the client you want to drop and that's it.  I tested this on an enterprise wireless network and it failed to work.
My suspicion is that the app uses ARP spoofing and hence why it doesn't work on enterprise networks that have DHCP and ARP protection. Will need to do some packet captures to confirm this.