Tag Archives: Debian

Debian

Recommendations of Webmin for Debian users

< What is “Webmin”? >
“Webmin” is a configuration tool with WEB based UI written in Perl. It can run on Linux / UNIX / Windows / OSX. When I install Debian to my computer, I install “Webmin”. Basically I use it to edit configuration files, because I don’t need to remember where are configuration files. “Webmin” can control starting and stopping of any services. “Webmin” has so many convenient functions. But it’s too heavy for me to explain everything about it. If you want to know about “Webmin” more, please check Webmin – Wikipedia and http://www.webmin.com/.

< Installation on Debian >
Please check latest version of webmin on http://www.webmin.com/. Please replace the red URL to the newest one when you check the official web site. Execute the commands below as root to install webmin.

root@myhost:~# cd /tmp
root@myhost:/tmp# wget http://prdownloads.sourceforge.net/webadmin/webmin_1.690_all.deb
root@myhost:/tmp# dpkg -i webmin_1.690_all.deb
root@myhost:/tmp# apt-get -f install

After the command “dpkg -i webmin_1.690_all.deb“, apt show you any warnings. After that, please execute “apt-get -f install” to install required software for webmin.

< For security >
By default configuration, webmin can be accessed only from local network. I have never changed it, because of the security. I always use SSH port transfer or any kind of VPN to use webmin from the internet. You don’t need to allow webmin to be accessed directly from the internet.

< SSH port transfer >
If your user name is “abcd” and domain is “example.com“, SSH login with port transfer for webmin is a command line below.

$ ssh -L 10000:localhost:10000 abcd@example.com

This command line is for Linux / UNIX / OSX. You can also use IP address instead of domain.

< Login to Webmin >
Use any browser to access “https://localhost:10000/“. You will see untrusted message like below.
untrusted_001
It is an example of Firefox. Please push “Add Exception” if you use Firefox.
untrusted_002
First time, you need to login as root. If you don’t want to use root to login to webmin, you can add any user for webmin.
webmin_login

< Which language do you use? >
Default language for webmin is English. If you want to change global language setting, please check the navigation and picture below.
[ Webmin ] – [ Webmin Configuration ] – [ Language ]
webmin_change_language_001
You can select default language and character code for webmin user interface by the function above. If you want to change personal language or theme, please check the navigation and picture below.
[ Webmin ] – [ Change Language and Theme ]
webmin_change_language_002

< Webmin theme >
I want to explain how to add webmin users, but before adding webmin users, I need to explain about my webmin theme.
[ Webmin ] – [ Webmin Configuration ] – [ Webmin Themes ]
You can select themes for Webmin UI. I always use “MSC.Linux Theme“. Please choose a theme you want to use. But during following my procedure on this post, it’s easy to follow using “MSC.Linux Theme“.
webmin_theme

< Add system user >
I always add system user before adding webmin user. Because I use UNIX login for webmin. You can add users for your operation system at the navigation below. I use this function instead of “adduser” command.
[ System ] – [ Users and Groups ] – [ Create a new user ]
I basically use default settings for new user. I only change password.
webmin_users

< Add Webmin user >
You can add users for webmin at the navigation below. You need to select functions of webmin to allow the user can control. I always use UNIX authentication for PASSWORD.
[ Webmin ] – [ Webmin Users ] – [ Create a new Webmin user ]
After I add webmin user, I always re-login webmin on the new user.
webmin_add_webminuser
You can find the module list like below.
webmin_select_modules
If you want to control everything like an administrator, please click “Select all” to select all functions.

< Control system and service >
[ System ] – [ Bootup and Shutdown ]
This picture shows functions on the bottom of the page.
webmin_control_services

< About Webmin modules >
When I have spare time, I will update this post or write new post about some modules for webmin.

Reverse proxy on nginx on Raspberry pi

< Ready to install >
You need Debian wheezy to follow my procedure. Not only for Raspberry Pi.

< Why I use Raspberry Pi >
Reverse proxy is simple function. Basically it’s too easy task for general personal computers or any servers. Raspberry Pi is not so powerful, but it’s energy saving computer. It’s not expensive. Anyone can buy it all over the world. It’s enough for reverse proxy on nginx. That’s why I choose Raspberry Pi for reverse proxy server and wrote this post.

< Installing nginx >
Execute command below as root.

apt-get install nginx

That’s all.

< Edit config file >
Edit default config file.

nano /etc/nginx/sites-available/default

My “/etc/nginx/sites-available/default” is like below.

server {
listen 80;
server_name mydomain.net;

location / {
proxy_pass http://127.0.0.1:8080;
}
}

This config transfer accesses “mydomain.net” to 8080 port of local Apache server on Raspberry Pi.

< Add proxy config file >
Add a file for proxy settings.

nano /etc/nginx/conf.d/proxy.conf

My “/etc/nginx/conf.d/proxy.conf” is like blow.

# Header
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-Host $host;
proxy_set_header X-Forwarded-Server $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

# Timeout
proxy_connect_timeout 60;
proxy_read_timeout 90;
proxy_send_timeout 60;

# Buffer
proxy_buffering on;
proxy_buffer_size 8k;
proxy_buffers 100 8k;

# Cache
proxy_cache_path /var/cache/nginx/mydomain.net levels=1:2 keys_zone=cache_$
proxy_temp_path /var/cache/nginx/temp;

proxy_cache_valid 200 2h;
proxy_cache_valid 302 2h;
proxy_cache_valid 301 4h;
proxy_cache_valid any 1m;

Also you need to make cache dir as root.

mkdir /var/cache/nginx

< Start nginx >

service nginx start

How you think about this procedure? So easy?

bochs on Raspberry Pi

< x86 on ARM >
I try to run DOS on Debian wheezy on Raspberry Pi.
( Windows95 is also possible, but it’s too slow )

< Install “bochs” >
Installing “bochs” is very easy.
Command line is as below.

root@myhost:~# apt-get install bochs bochs-x bochs-sdl bochs-svga

< Generate hard disk image >
Execute “bximage” on your Raspberry Pi.
I recommend to execute “bximage” as non-root user.
You should execute “bximage” as a user which use “bochs”.
It’s 2GB image sample.

$ bximage
========================================================================
                                bximage
                  Disk Image Creation Tool for Bochs
        $Id: bximage.c,v 1.34 2009/04/14 09:45:22 sshwarts Exp $
========================================================================
Do you want to create a floppy disk image or a hard disk image?
Please type hd or fd. [hd]
What kind of image should I create?
Please type flat, sparse or growing. [flat]
Enter the hard disk size in megabytes, between 1 and 129023
[10] 
2048
I will create a ‘flat’ hard disk image with
  cyl=4161
  heads=16
  sectors per track=63
  total sectors=4194288
  total size=2047.99 megabytes
What should I name the image?
[c.img] 
msdoshdd.img
Writing: [] Done.
I wrote 2147475456 bytes to msdoshdd.img.
The following line should appear in your bochsrc:
  
ata0-master: type=disk, path=”msdoshdd.img”, mode=flat, cylinders=4161, heads=16, spt=63

“bximage” said to add line “
ata0-master: type=disk, path=”msdoshdd.img”, mode=flat, cylinders=4161, heads=16, spt=63” to “.bochsrc”.

< Generate “.bochsrc” for MS-DOS >
Go to your home directory.
I use “nano” to edit text files.

$ cd /home/username
$ nano .bochsrc

My “.bochsrc” is as below.

megs: 64
romimage: file=$BXSHARE/BIOS-bochs-latest
vgaromimage: file=$BXSHARE/VGABIOS-lgpl-latest
display_library: sdl
ata0-master: type=disk, path=/home/username/msdoshdd.img, mode=flat, cylinders=4161, heads=16, spt=63
ata0-slave: type=cdrom, path=/home/username/MS-DOS-6.22.iso, status=inserted
boot: cdrom, disk
#keyboard_mapping: enabled=1, map=/usr/share/bochs/keymaps/x11-pc-us.map
log: bochsout.txt
clock: sync=realtime, time0=local

“MS-DOS-6.22.iso” is my MS-DOS bootable file. Please replace it to any iso bootable file you have. In my “.bochsrc”, mouse is unavailable. If you want to use mouse, please google about “How to edit bochsrc to use mouse”.

< Install VNC >
If you use HDMI display, you don’t need this step.
If you don’t use display, you need to install VNC server to remote X on Raspberry Pi.
Execute this command line as root.

root@myhost:~# apt-get install tightvncserver

Run this command line as a user which use “bochs”.

$ vncserver :1 -geometry 1024×768 -depth 24
You will require a password to access your desktops.
Password:
Verify:
Would you like to enter a view-only password (y/n)? 
n
New ‘X’ desktop is myhost:1

“:1″ means port “5901″.
“-geometry 1024×768″ means resolution.
“-depth 24″ means colors in bits.

< Execute bochs >
Please connect your VNC server on Raspberry Pi. ( or use “startx” with HDMI display )
And execute terminal. ( ex. LXTerminal )
Execute bochs on terminal.

$ bochs

Sometimes bochs ask you like this syntax.

A PANIC has occurred.  Do you want to:
  cont       – continue execution
  alwayscont – continue execution, and don’t ask again.
               This affects only PANIC events from device [MEM0 ]
  die        – stop execution now
  abort      – dump core
  debug      – hand control to gdb

I always answer “alwayscont”.

< To be honest >
I tried to install Windows95.
But it needs FD images of DOS and Windows3.1. ( My Windows95 is upgrade version )
It was troublesome for me.
So I changed my goal.