Administração de Sistemas via Web com Webmin

Colaboração: Nelmar José Alvarenga

Data de Publicação: 01 de Dezembro de 1999

O Nelmar me enviou um documento bastante detalhado sobre o software Webmin, que permite a administração de sistemas Unix via Web. Nós utilizamos este software aqui na Unicamp e temos obtido excelentes resultados.

Há algum tempo tenho usado uma excelente ferramenta de administracao de maquinas UNIX. Seu nome: Webmin, que pode ser encontrado "free" em

  http://www.webmin.com/webmin/ 
  Release 0.74 de 10/10/1999

e que permite toda a configuracao, manutencao, dentre muitas outras tarefas do cotidiano de um Adminstrador de Sistemas UNIX, serem facilmente executadas via web-browser facilitando tarefas e permitindo que de um ponto qualquer de sua rede, voce possa ate mesmo dar shutdown ou rebootar sua Workstation !!!)

Encontrei o Webmin quando procurava algo para facilitar a administracao do meu Apache --- e olha o que encontrei ! Uma ferramenta que administra o Apache e muito, muito mais !!!

Pré-requisitos: uma maquina UNIX (Solaris, AIX, OSF1, HP-UX, IRIX, LINUX, etc ... !) e PERL 5.003 instalado. OBS: Voce nao precisa do Apache instalado. Mas se tiver, o Webmin nao ira conflitar (pois usa uma porta TCP 10000 e ajudará voce a administra-lo !

O processo de instalacao é muito simples. Veja um exemplo de uma instalacao que executei recentemente, em ambiente Solaris 2.6 (mas ja executei instalacoes em Solaris 2.5.1 e LINUX de diversas distribuicoes, com sucesso):

Fazendo logon como "root" (adicao de pacote PERL e

  install do Webmin):
  $ su        
  Password: 
  # pwd
  /usr/home/qndw

OBS: Instalando como abaixo, e possivel DESINSTALAR o pacote PERL (obtido em http://sunfreeware.com) pelo "admintool" .

  # pkgadd -d perl-5.005_03-sol26-sparc-local
  
  The following packages are available:
    1  LWperl     perl
                  (sparc) 5.005_03
  
  Select package(s) you wish to process (or áll' to
  process
  all packages). (default: all) [?,??,q]: <enter>
  Processing package instance <LWperl> from
  </usr/home/qndw/perl-5.005_03-sol26-sparc-local>
  
  perl
  (sparc) 5.005_03
  Larry Wall
  
  The selected base directory </usr/local> must exist
  before
  installation is attempted.
  
  Do you want this directory created now [y,n,?,q] y
  <enter>
  Using </usr/local> as the package base directory.
  ## Processing package information.
  ## Processing system information.
  ## Verifying disk space requirements.
  ## Checking for conflicts with packages already
  installed.
  ## Checking for setuid/setgid programs.
  
  Installing perl as <LWperl>
  
  ## Installing part 1 of 1.
  /usr/local/README.solaris.perl
  /usr/local/bin/a2p
  ``` .
  /usr/local/man/man1/xsubpp.1
  [ verifying class <none> ]
  /usr/local/bin/perl <linked pathname>
  /usr/local/bin/pstruct <linked pathname>
  
  Installation of <LWperl> was successful.
  
  # 
  
  Instalando o Webmin (versao 0.74) no meu diretorio : 
  # tar -xvf webmin-0.74.tar
  x webmin-0.74, 0 bytes, 0 tape blocks
     ...
  
  # cd webmin-0.74
  # ./setup.sh
  ***********************************************************************
  *            Welcome to the Webmin setup script,
  version 0.74         *
  ***********************************************************************
  Webmin is a web-based interface that allows Unix-like
  operating
  systems and common Unix services to be easily
  administered.
  
  Installing Webmin in /usr/home/qndw/webmin-0.74 ...
  
  ***********************************************************************
  Webmin uses separate directories for configuration
  files and log files.
  Unless you want to run multiple versions of Webmin at
  the same time
  you can just accept the defaults.
  
  Config file directory [/etc/webmin]:
  Log file directory [/var/webmin]: 
  
  ***********************************************************************
  Webmin is written entirely in Perl. Please enter the
  full path to the
  Perl 5 interpreter on your system.
  
  Full path to perl (default /usr/local/bin/perl): 
  
  Testing Perl ...
  Perl seems to be installed ok
  
  ***********************************************************************
  For Webmin to work properly, it needs to know which
  operating system
  type and version you are running. Please select your
  system type by
  entering the number next to it from the list below
   -----------------------------------------------------------------------
    1) Sun Solaris                          2) Caldera
  OpenLinux                  
    3) Redhat Linux                         4) Slackware
  Linux                    
    5) Debian Linux                         6) SuSE
  Linux                         
    7) Mandrake Linux                       8) Delix DLD
  Linux                    
    9) MkLinux                             10) FreeBSD  
                           
   11) BSDI                                12) HP/UX    
                           
   13) SGI Irix                            14)
  DEC/Compaq OSF/1                   
   15) IBM AIX                             16) SCO
  UnixWare                       
   17) SCO OpenServer                      18) MacOS
  Server X                     
   ---------------------------------------------------------------------------
  Operating system:  1
  
  Please choose which version of Sun Solaris you are
  running, by entering
  the number next to it from the list below
   ---------------------------------------------------------------------------
    1) Sun Solaris 2.5                      2) Sun
  Solaris 2.5.1                  
    3) Sun Solaris 2.6                      4) Sun
  Solaris 7                      
   ---------------------------------------------------------------------------
  Version: 3
  
  Operating system name:    Sun Solaris
  Operating system version: 2.6
  
  ***********************************************************************
  Webmin uses its own password protected web server to
  provide access
  to the administration programs. The setup script needs
  to know :
   - What port to run the web server on. There must not
  be another
     web server already using this port.
   - The login name required to access the web server.
   - The password required to access the web server.
   - The hostname of this system that the web server
  should use.
   - If the webserver should use SSL (if your system
  supports it).
   - Whether to start webmin at boot time.
  
  Web server port (default 10000): 
  Login name (default admin): <enter>
  Login password: <digite uma senha>
  Web server hostname (default spows01): 
  The Perl SSLeay library is not installed. SSL not
  available.
  Start Webmin at boot time (y/n): y
  ***********************************************************************
  Creating web server config files..
  ``` done
  
  Creating access control file..
  ``` done
  
  Inserting path to perl into scripts..
  ``` done
  
  Creating start and stop scripts..
  ``` done
  
  Copying config files..
  ``` done
  
  Configuring Webmin to start at boot time..
  Created init script /etc/init.d/webmin
  ``` done
  
  Creating uninstall script /etc/webmin/uninstall.sh ..
  ``` done
  
  Changing ownership of Webmin to root:bin ..
  ``` done
  
  Attempting to start Webmin mini web server..
  Starting Webmin server in /usr/home/qndw/webmin-0.74
  ``` done
  
  ***********************************************************************
  Webmin has been installed and started successfully.
  Use your web
  browser to go to
  
    http://spows01:10000/
  
  and login with the name and password you entered
  previously.
  
  # pwd
  /usr/home/x845/webmin-0.74

A partir daqui, basta ir a outra maquina de sua rede com Web-browser (IE ou Netscape ou similar) e acessar

          http://<ip_de_sua_estacao_unix>:10000/

digitar "admin" e senha e voce tera sua estacao a suas maos !!! Portanto, so mais uma dica: MUITO CUIDADO COM O QUE ESCOLHER PARA EXECUTAR (ex: Reboot) POIS TUDO FUNCIONA PERFEITAMENTE (inclusive um gerenciador de arquivos em Java que definitivamente acaba com a necessidade de edicao de arquivos via "vi" !!! Tudo agora via browser !