Using tcp_wrappers

To a lot of newbies, including myself, designing and setting up a proper firewall requires a lot of technical knowledge, experiences and perhaps expertise. I mean a real perimeter firewall, not those you play at home with your ADSL router type of firewall.

Before we talk about firewall, does linux system provides any form of protection over remote ssh attack? A simple one that needs only a few lines, to at least not allowing anybody trying to ssh in?

Alright, this is what we are going to talk about - 'tcp_wrappers'.

Under /etc, you'll find hosts.allow and hosts.deny. If you don't get any of the file, you could just create it with your favourite editor, i use vi.

Straight to the point, stop beating around the bush...

Under /etc/hosts.allow

# You want to allow remote users telnet into your host, but only LAN - trusted users
in.telnetd: 192.168.1.0/255.255.255.0 : Allow

Under /etc/hosts.deny

#You'd only need to deny everything :
in.telnetd: ALL : Deny

Under normal circumstances, the 2 files above means hosts.deny will deny anything trying to connect to this protected host, but whatever listed in hosts.allow will be allow.

Clear? Okay, lay man term, "Deny everything, only allow what listed in hosts.allow file". Get it?

Oh yeah, changing the above 2 files, you don't have to restart anything, it'll work after you save the files.

What if i want to log all those attempted in? Check this out -

in.telnetd: ALL : spawn (echo Security notice from host `/bin/hostname`; \
echo; /usr/sbin/safe_finger @%h ) | \
/bin/mail -s "%d-%h security" admin@email.com & \
: twist ( /bin/echo -e "\n\nWARNING connection not allowed. Your attempt has been logged.
/etc/hosts.deny

Simple, huh??

regards,
Skywalker

Which interface is ethX?

Come across this useful tips by RedHat Magazine's site..

When you're troubleshooting a machine (mostly servers - in my case) you may be wondering which NIC (more than 1 of course) is the eth0/1/2??

Use this command - "/sbin/ethtool -p eth0 5"

The eth0 card will blink 5 times, without interrupting the network traffic. I have not tried this cuz i'm composing this blog at my dual-boot windows machine.

Well, i find that mii-tool does help too - "/sbin/mii-tool"

eth0: negotiated 100baseTx-HD, link ok
eth1: no link

Simple, right?

regards,
Skywalker

Inori ~ Your Raise Me Up

I got crazy about this song - Inori - You Raise Me Up - By Lena Park

http://www.youtube.com/watch?v=BNZnvi4CiXg

I fall in love again... In love with this song...

You can get the lyrics here - English version sung by Celtic Woman and Josh Groban, but this is the Japanese version.

Feel free to choose whichever version you like.. it's a lovely song.

Close your eyes and enjoy the rhythm of the song...

I hope you'll like it.

regards,
GS

HEROES - Season 1

Have you ever watch 23 episodes of tv series in just 2.5 days???

I did...

It was HEROES - Season 1

Maybe i'm just too lonely during the weekend especially near to upcoming festive holiday and i've got no working mood, thus, i bought the whole season 1 of HEROES dvd.

It's been long time i have never got attracted to TV series that suck me into it so much. I've got addicted, can't stop, can't leave my laptop and can't help to finish it, at least to the end of the season's last episode.

It's breath taking story, the story line was always a bunch of X-Men trying to save the world, but this it's different from the plain old X-Men from the movie series which you'll see so much of special effects and the entire story has to be told in about 2 hours.

HEROES talks about a Japanese guy - Hiro Nakamura, who accidentally saw the incident of Apple city about to be blown off by a bomb, the story then starts from there. How Hiro trying to convince another heroes to help him to save the city.

It's not about a single person being a hero, that's what i understand by the movie title "HEROES" means. Because there are bunch of guys with super power putting together stop the city from being blown into pieces. But these heroes are not ready to save the city at first, through some string pullings putting about 10 different human with super power together, they are trying to do what they felt their responsibility to save the city.

Throughout the whole save the world mission, all of them have problems on their own, a cute kid with power to talk to machines and instructs them to do what he wants - he withdraw money from ATM by just touching it, holly God, i wish i have that!! But little Micah has his problems too, cause his father is jailed and his mom had to strip in front of a web cam in order to survive.

A guy dreamed that he could fly, and after a few times of dreaming, he really jump out of the building... Well, this lucky bastard is saved by someone who can really fly... but why does he dreamed that he could fly but instead he's almost dead jumping off the building?

An artist, could paint the future, but he also painted himself being kill by a serial killer... too bad huh.. But if not because of him, this series would not start, because he's the one painted the city would be blown off.

A cute cheer leader who wants to be a normal person, but she tried to jump off from building, she's not flying obviously, but she just can't die... her wound would cure by itself, weird, she's sad because she can't kill herself... But she's the cause of why these group of heroes want to save the world!

With so many story lines putting together, you won't get bored by just 1 hero acting from start to end.

Can the future be change? Can the past be changed? If the history can be changed, what will happen to me? Can my previous mistakes be undone?

Very interesting point, if i could change my previous mistakes, will i be myself anymore?

regards,
GS

Resident Evil - Extinction

At the end of the movie, is human being in extinction, yet?

I am having a lots of pressure at work, not really happy. This is a true feelings, when everybody is envy over my overseas traveling, i come back with a sour face.

Thus, watching a movie without needing to think is a good cure of a pathetic loser.

Almost from start to end, it's all fighting scenes with guns and bombs, to kill in order to survive, does Alice (Milla Jovovich) feel pathetic also?

Did i say she's a killer, killing thousands of... are they still humans?? Well, anyway, i think those beings are just monsters, in computer terms we call those programs cannot be killed - zombie.

This episode Alice have the super power of what Sylar/Peter Petrelli (in Heroes) had, oh yeah.. because Ali Larter is also in this movie too :)

Well, what attracts my eye balls besides the 2 ladies above, is Ashanti... oh my god, she's one hell of a hot nurse.. :)

Anyway, all fighting scenes leads to the end of good vs bad, and of course you'd expect the good guy wins, but what's next?? Clone War perhaps ??

I'm walking back to my apartment thinking that there'll be forth episode coming out, when will Resident Evil ends? I thought i started from a small house, oh i mean, a lab, but the virus spreads to the world??

Alaska is the only place for human, go there, you'll be safe... is it?

regards,
GS

What a pathetic...

Well, i just thought of the word "pathetic" could very well describe me.. and my feelings.

1 month of oversea business project, i'm staying in a foreign land, started to pick up a bit of the foreign language, i thought i'd like this, but i don't.

How pathetic i am?? I'm watching Resident Evil - Extinction on my own, with 3 couples in the cinema??!!!

Only 7 people watching this movie in a city's famous mall.

I feel so lonely, sad and then pathetic on my own.

My colleague got a local girl friend here, enjoying one of the biggest festival celebration here in this foreign land, but i'm alone in the apartment, day-dreaming.

I started to miss home, even though my bedroom look like shit, but, hey.. i'm home... i've got friends, i can visit friends... it's my home, i can do whatever i like.

I think i started to have the feelings of home sick now... Even if there's no one at home, but i'll feel more comfortable at home.

regards,
GS