Dotaz: problem s DNS

[jany2]

Popisem najprv problem:

Mam ADSL internet a ako hlavni router pouzivam RB450 (mikrotik). Dalej mam v sieti jeden Ubuntu 192.168.1.3, na ktorom bezi okrem ineho LAMP, proftpd ... Na mikrotiku sa da velmi primitivnym sposobom nastavit DNS, jednoducho sa ide cez IP -- DNS a napise sa tam Name a IP adresa. Cize ja som si zvolil napr name www.moj-server.sk a adresu som dal 192.168.1.3. Vsetko pekne funguje (samozrejme len z vnutra :) ). Problem ale nastane ak ADSL spadne. Vtedy sa neviem dostat na web cez www.moj-server.sk, ale musim ist cez 192.168.1.3 (taktiez nefunguje proFTPd).

Predpokladam, ze ak sa budem chciet dostat na svoj web cez domenove meno, tak bude treba na linuxe nakonfigurovat BIND DNS Server. Nainstalovany ho uz mam :) ale nemam s tym absolutne ziadne skusenosti. Kedze som slabsi linuxak, tak som si davnejsie nainstaloval aj webmin, ma to krasne web rozhranie, ale aj tak neviem ako to nastavit. Zatial som okolo toho nic nestudoval, ale nieco sa pokusim najst a nastudovat, ale moc velke nadeje si nedavam Ak by niekto vedel poradit, tak to by bolo fajn

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Odpovědi

[NN]

Bude bohate stacit staticky zapis do /etc/hosts:

192.168.0.1 www.moj-server.sk

a zadny bind nemusis konfigurovat.

NN

[jany2]

preco 192.168.0.1 ? ked mam server 192.168.1.3 Teraz som ho upravil a mam to takto

127.0.0.1       localhost
127.0.1.1       moj-server.moj-serversk    moj-server
192.168.1.3     www.moj-server.sk
# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts

Bude to OK ?

[azurIt]

Ano, kolega hore urobil maly preklep.

[jany2]

inak spomenul som, ze ak je ADSL down, tak nefunguje ani FTP, aj ked na FTP sa pripajam cez IP adresu nie domenove meno. To by malo predsa fungovat, nie ?

[azurIt]

Nemas nahodou na FTP serveri (pripadne v inetd) nastavene, aby sa bindoval na ten host miesto IP adresy ? Logicky, ak host nevie prelozit, nevie, na aku IP sa ma bindnut takze sa nespusti.

[jany2]

Myslim, ze v proftpd.conf to nieje nastavene, dam sem pre istotu conf

#
# /etc/proftpd/proftpd.conf -- This is a basic ProFTPD configuration file.
# To really apply changes reload proftpd after modifications.
# 

# Includes DSO modules
Include /etc/proftpd/modules.conf

# Set off to disable IPv6 support which is annoying on IPv4 only boxes.
UseIPv6                on
# If set on you can experience a longer connection delay in many cases.
IdentLookups            off

ServerName            "Debian"
ServerType             inetd
DeferWelcome            off

MultilineRFC2228        on
DefaultServer            on
ShowSymlinks            on

TimeoutNoTransfer        600
TimeoutStalled            600
TimeoutIdle            1200

DisplayLogin                    welcome.msg
DisplayChdir                   .message true
ListOptions                    "-l"

DenyFilter            \*.*/

# Use this to jail all users in their homes 
DefaultRoot            /home

# Users require a valid shell listed in /etc/shells to login.
# Use this directive to release that constrain.
# RequireValidShell        off

# Port 21 is the standard FTP port.
Port                21

# In some cases you have to specify passive ports range to by-pass
# firewall limitations. Ephemeral ports can be used for that, but
# feel free to use a more narrow range.
# PassivePorts                  49152 65534

# If your host was NATted, this option is useful in order to
# allow passive tranfers to work. You have to use your public
# address and opening the passive ports used on your firewall as well.
# MasqueradeAddress        1.2.3.4

# This is useful for masquerading address with dynamic IPs:
# refresh any configured MasqueradeAddress directives every 8 hours
<IfModule mod_dynmasq.c>
# DynMasqRefresh 28800
</IfModule>

# To prevent DoS attacks, set the maximum number of child processes
# to 30.  If you need to allow more than 30 concurrent connections
# at once, simply increase this value.  Note that this ONLY works
# in standalone mode, in inetd mode you should use an inetd server
# that allows you to limit maximum number of processes per service
# (such as xinetd)
MaxInstances            30

# Set the user and group that the server normally runs at.
User                proftpd
Group                nogroup

# Umask 022 is a good standard umask to prevent new files and dirs
# (second parm) from being group and world writable.
Umask                022  022
# Normally, we want files to be overwriteable.
AllowOverwrite            on

# Uncomment this if you are using NIS or LDAP via NSS to retrieve passwords:
# PersistentPasswd        off

# This is required to use both PAM-based authentication and local passwords
# AuthOrder            mod_auth_pam.c* mod_auth_unix.c

# Be warned: use of this directive impacts CPU average load!
# Uncomment this if you like to see progress and transfer rate with ftpwho
# in downloads. That is not needed for uploads rates.
#
# UseSendFile            off
 
<Directory ~/jany>
 <Limit WRITE>
 AllowUser jany
 DenyAll
 </Limit>
 </Directory>
 
 <Directory ~/lubo>
 <Limit WRITE>
 AllowUser lubo
 DenyAll
 </Limit>
 </Directory>

 


TransferLog /var/log/proftpd/xferlog
SystemLog   /var/log/proftpd/proftpd.log

<IfModule mod_quotatab.c>
QuotaEngine off
</IfModule>

<IfModule mod_ratio.c>
Ratios off
</IfModule>


# Delay engine reduces impact of the so-called Timing Attack described in
# http://security.lss.hr/index.php?page=details&ID=LSS-2004-10-02
# It is on by default. 
<IfModule mod_delay.c>
DelayEngine on
</IfModule>

<IfModule mod_ctrls.c>
ControlsEngine        off
ControlsMaxClients    2
ControlsLog           /var/log/proftpd/controls.log
ControlsInterval      5
ControlsSocket        /var/run/proftpd/proftpd.sock
</IfModule>

<IfModule mod_ctrls_admin.c>
AdminControlsEngine off
</IfModule>

#
# Alternative authentication frameworks
#
#Include /etc/proftpd/ldap.conf
#Include /etc/proftpd/sql.conf

#
# This is used for FTPS connections
#
#Include /etc/proftpd/tls.conf

# A basic anonymous configuration, no upload directories.

# <Anonymous ~ftp>
#   User                ftp
#   Group                nogroup
#   # We want clients to be able to login with "anonymous" as well as "ftp"
#   UserAlias            anonymous ftp
#   # Cosmetic changes, all files belongs to ftp user
#   DirFakeUser    on ftp
#   DirFakeGroup on ftp
# 
#   RequireValidShell        off
# 
#   # Limit the maximum number of anonymous logins
#   MaxClients            10
# 
#   # We want 'welcome.msg' displayed at login, and '.message' displayed
#   # in each newly chdired directory.
#   DisplayLogin            welcome.msg
#   DisplayChdir        .message
# 
#   # Limit WRITE everywhere in the anonymous chroot
#   <Directory *>
#     <Limit WRITE>
#       DenyAll
#     </Limit>
#   </Directory>
# 
#   # Uncomment this if you're brave.
#   # <Directory incoming>
#   #   # Umask 022 is a good standard umask to prevent new files and dirs
#   #   # (second parm) from being group and world writable.
#   #   Umask                022  022
#   #            <Limit READ WRITE>
#   #            DenyAll
#   #            </Limit>
#   #            <Limit STOR>
#   #            AllowAll
#   #            </Limit>
#   # </Directory>
# 
# </Anonymous>

a v init  neviem, kde by som to mal hladat

[azurIt]

ProFTPd spustas cez inetd, takze este inetd.conf (alebo xinetd.conf pripadne to, co pouzivas). Mozes skusit tiez napr.:

cd /etc
grep -R -i moj-server.sk *

[jany2]

toto to na mna vyhodilo

grep: blkid.tab: No such file or directory hosts:127.0.1.1 moj-server.moj-server.sk moj-server hosts:192.168.1.3 www.moj-server.sk mailname:moj-server.moj-server.sk grep: rc0.d/K25hwclock.sh: No such file or directory grep: rc6.d/K25hwclock.sh: No such file or directory ssmtp/ssmtp.conf:hostname=moj-server.moj-server.sk

[azurIt]

nabuduce to daj v nejakom tvare, ktory sa da normalne citat :) tento riadok v /etc/hosts je poriadna kravina:
127.0.1.1 moj-server.moj-server.sk moj-server

skus tam nastavit IPcku serveru, mohlo by to pomoct.

[jany2]

Sorry za ten vypis :)

Skusim to nastavit ... nebudem teraz schvalne odpajat ADSL aby som to preveril, ale ked to vypadne, tak to vyskusam, ci to pojde, zatial dik