Linux

@clucas is playing with UC320W

Posted on by clucas

I have received at work this Cisco Small Business units to test it b efore we can sell it to customers.

It seems really well. It is well designed (some linux distro is behind), and customized. I love all these features and smart/quickly applied and in action.

UC320W is a good prodoct for Small business office.

Astuce : ping et fragmentation

Posted on by clucas

Voici une petite astuce (ok à deux balles) afin de faire avec votre Linux préféré la même chose que vous faîtes avec votre IOS (Cisco) via la commande :

R# ping your_host size 1520 df-bit

Vous devrez faire avec votre linux :

LinuxBox:~# ping -M do -s 1520 your_host
[...]
LinuxBox:~#

Et avec un OpenBSD :

OpenBSDBox# ping -D -s 1520 your_host

For fun : ‘ena’ C program

Posted on by clucas

I think it has been really often done in the past, but for fun :

For those of you whom use a lot of xterm, I think it have happen you mistake tape an ‘ena’ command in your sh friend shell program 🙂
It can be funny to have a result on your stdout other than :

Commande « ena » non trouvée, vouliez-vous dire :
 La commande « enna » issue du paquet « enna » (universe)
 La commande « eva » issue du paquet « eva » (universe)
 La commande « enca » issue du paquet « enca » (universe)
 La commande « ent » issue du paquet « ent » (universe)
 La commande « env » issue du paquet « coreutils » (main)
ena : commande introuvable

It can be funny to have :

clucas@pluton:~$ ena
Password:
Building configuration...
[OK]
Proceed with reload? [confirm]
Connection closed by foreign host.

Be quiet, you are on a Unix based system and I will not disclose your password ;)

You can have the full source code of this here.

It could be really funny to send it by a socket, but I don’t have written it in the code.

Apache2 and buffered transaction

Posted on by clucas

If you must have an Apache2 webserver which is not buffering (realtime printf) transaction, you must remove ‘deflate‘ : 

root@plop~# a2dismod deflate
Module deflate disabled.
Run '/etc/init.d/apache2 restart' to activate new configuration!
root@plop~# /etc/init.d/apache2 restart
Restarting web server: apache2 ... waiting .
root@plop~#

Ping tool : How to learn some new stuff

Posted on by clucas
We always can learn some useful new thing in reading manual. This is what I have done and lear an interesting features by means of ping -R.
What we can read in ping(8) on a Linux System :

-R     Record route.  Includes the RECORD_ROUTE option in the ECHO_REQUEST
       packet and displays the  route  buffer  on returned  packets.
       Note  that the IP header is only large enough for nine such routes.
       Many hosts ignore or discard this option.

It can be really useful such as :

plop:~# traceroute -n 217.169.240.154
traceroute to 217.169.240.154 (217.169.240.154), 30 hops max, 40 byte packets
 1  217.169.242.252  0.628 ms  0.845 ms  1.091 ms
 2  217.169.240.105  0.419 ms  0.455 ms  0.490 ms
 3  217.169.240.90  0.802 ms  0.851 ms  0.890 ms
 4  217.169.240.154  11.720 ms * *
plop:~# ping -n -R 217.169.240.154
PING 217.169.240.154 (217.169.240.154) 56(124) bytes of data.
64 bytes from 217.169.240.154: icmp_seq=1 ttl=252 time=12.3 ms
NOP
RR:     217.169.242.220
        217.169.240.106
        217.169.240.89
        217.169.240.153
        217.169.240.154
        217.169.240.114
        217.169.240.85
        217.169.240.105
        217.169.242.252

You can discover by which routers your packet are routed 🙂 In my case, you can see that my packets don’t take the same path.