BGP – aggregate-address

To advertise a summary route in BGP, aggregate-address is used. 

Example

The topology is:

R1 --- FR --- R2

BEFORE summarize the route:

R1 – show ip bgp

R2 – show ip bgp

To summarize the 2.x.x.x network, aggregate-address is used.

R2(config)# router bgp 200

R2(config-router)# aggregate-address 2.2.0.0 255.255.252.0

R1 – show ip bgp

R2 –show ip bgp

A summary route

*> 2.2.0.0/22       0.0.0.0                            32768 i

is advertised to R1.

Note that by default the aggregate AND ALL the specific routes are advertised.  If you want to suppress the specific routes, use the “summary-only” argument.

R2(config-router)#aggregate-address 2.2.0.0 255.255.252.0 summary-only

R1 – show ip bgp

 

R2 – show ip bgp

Notice that the specific routes are suppressed, only the summarized routes are advertised to the neighbors.

2 attributes are displayed: aggregator and atomic aggregate.

The aggregator attribute identifies the router that performed the aggregation.  In this case it is 2.2.3.2.

The atomic-aggregate attribute tells us that some information is lost because of aggregate.

My CCIE Lab Countdown

After postponing my R&S lab test several times for lots of reasons (or excuses precisely), finally confirmed 18 Sep in Tokyo for my first attempt.

84 days ta go....

Toggling rdesktop full screen mode

To rdesktop your Windows host is easy:

rdesktop -f

but the next question is, how to get back to your original Linux host?

The answer is:

Ctrl-Alt-Enter

Use it to toggle between full-screen and non-full screen mode!

Other posts on rdesktop:
http://pandaeatsbamboo.blogspot.com/2008/03/share-clipboard-and-map-network-drive.html
http://pandaeatsbamboo.blogspot.com/2008/02/remote-desktop-from-linux-rdesktop.html

iPhone 3G makes its debut

Connect to a WPA-PSK wireless network on Slax

My environment: IBM Thinkpad T60 Centrino + SLAX 6.0.7 on my USB flash disk

Slax is a very lightweight and portable linux OS and I have just tried it on my USB flash disk, it is so easy to use that I can build it from stretch and connect to my home wifi within half an hour. Here is a short tutorial in how to connect it to my WPA-PSK protected wireless network.

1. Get your Slax here:
http://www.slax.org/get_slax.php

You can either burn it on your CD or download and extract the tarball to your USB flash disk. Run the bootinst.bat or bootinst.sh to make it bootable.

2. Download wpa_supplicant from http://www.slax.org/modules.php?action=detail&id=533. Move this module into /mnt/sdb1/modules, where sdb1 is the USB flash disk in my case.

3. Create the wpa_supplicant.conf config file in /mnt/sdb1/rootcopy/etc. Here is an example:

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=0
eapol_version=1
#ap_scan=0
#fast_reauth=1

network={
ssid="pandassid"
key_mgmt=WPA-PSK
proto=WPA
pairwise=TKIP
group=TKIP
psk="ilovethisblog"
}

4. Reboot it and then run this in your terminal:
wpa_supplicant -d -iwlan0 -c/etc/wpa_supplicant.conf -Dwext

5. You should receive confirmation on the terminal saying your key is accepted. Open another terminal and run the following:

iwconfig wlan0 essid pandassid
dhcpcd -G 192.168.1.0 wlan0

6. Done!!

Enable World Mode

I have a -W 7921 wireless phone and -N 1242 autonomous wireless access point, it takes me some time to troubleshoot why it can't get connected. The answer is world mode. When you enable world mode, the AP adds channel carrier set information to its beacon. Client devices with world mode enabled receive the carrier set information and automatically adjust their settings.

Example
int dot11radio 0
world dot11d country-code US both

Crontab

Not sure if you are interested to know. Normally when we do a crontab -e to edit or crontab -l to view a file, the physical file is located inside /var/log/cron. If you are logon as root, the file is /var/log/cron/root.

Installing VMWare Workstation 6.0.2 on 2.6.24 Kernel

My environment: Redhat Linux FC8 x86_64
VMWare version: Workstation 6.0.2

Tried to install VMWare workstation 6.0.2 on my Linux box with 2.6.24 kernel running and failed. Here is a quick how-to on how to resolve it:

1. Got your VMWare workstation tarball: VMware-workstation-6.0.2-59824.x86_64.tar.gz
2. Untar it
3. vmware-player-distrib/vmware-install.pl - when it asks you to run vmware-config.pl answer NO
4. Download VMWare patch vmware-any-any-update-116.tgz
All VMWare patch files here: http://groups.google.com/group/vmkernelnewbies/files
5. Untar your tarball
6. Run runme.pl, and when it asks you to run vmware-config.pl, answer YES
7. You know what to do after this step. If you don't know how to do, visit here.

Snapshot on Sony SNC-RZ30P Camera

Like other surveillance cameras, Sony provides a simple way to take snapshots via HTTP.

Take snapshot:
http://cam_ip/home/Capture.html

Get the picture:
wget http://cam_ip/oneshotimage.jpg

Cisco Dogbot