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1911 Views 1 Reply Latest reply: Dec 4, 2010 11:58 AM by Conwyn RSS

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Service commands ------ ?

Dec 4, 2010 11:17 AM

Dada Khalander 114 posts since
Sep 28, 2009

Hi All,

 

Can anyone please explain me the functionalities of the below three service commands? Thanks.

 

(config)# service finger

(config)# no service tcp-small-servers

(config)# no service udp-small-servers

 

 

 

Thanks & Regards,

S. Dada Khalander.

  • Conwyn 7,914 posts since
    Sep 10, 2008
    Currently Being Moderated
    1. Dec 4, 2010 11:58 AM (in response to Dada Khalander)
    Re: Service commands ------ ?

    Hi Dada

     

    The router runs services historically similar to UNIX.

     

    TCP small services are echo, chargen, discard, daytime

    UDP small services are echo, chargen, discard

     

    Finger lists logged on users.

     

    Security people normally like them disabled to stop Denial of Service attacks.

     

    You access them with telnet router-IP service-name

     

    telnet 1.2.3.4 daytime

     

    Regards Conwyn

     

    Here is the list

     

    pabxmod(config)#service ?
      alignment              Control alignment correction and logging
      compress-config        Compress the nvram configuration file
      config                 TFTP load config files
      dhcp                   Enable DHCP server and relay agent
      disable-ip-fast-frag   Disable IP particle-based fast fragmentation
      exec-callback          Enable exec callback
      exec-wait              Delay EXEC startup on noisy lines
      finger                 Allow responses to finger requests
      hide-telnet-addresses  Hide destination addresses in telnet command
      linenumber             enable line number banner for each exec
      nagle                  Enable Nagle's congestion control algorithm
      old-slip-prompts       Allow old scripts to operate with slip/ppp
      pad                    Enable PAD commands
      password-encryption    Encrypt system passwords
      prompt                 Enable mode specific prompt
      pt-vty-logging         Log significant VTY-Async events
      sequence-numbers       Stamp logger messages with a sequence number
      slave-log              Enable log capability of slave IPs
      tcp-keepalives-in      Generate keepalives on idle incoming network connections
      tcp-keepalives-out     Generate keepalives on idle outgoing network connections
      tcp-small-servers      Enable small TCP servers (e.g., ECHO)
      telnet-zeroidle        Set TCP window 0 when connection is idle
      timestamps             Timestamp debug/log messages
      txacc-accounting       Enable transmit credit accounting
      udp-small-servers      Enable small UDP servers (e.g., ECHO)

    (config)#service ?

      alignment              Control alignment correction and logging

      compress-config        Compress the nvram configuration file

      config                 TFTP load config files

      dhcp                   Enable DHCP server and relay agent

      disable-ip-fast-frag   Disable IP particle-based fast fragmentation

      exec-callback          Enable exec callback

      exec-wait              Delay EXEC startup on noisy lines

      finger                 Allow responses to finger requests

      hide-telnet-addresses  Hide destination addresses in telnet command

      linenumber             enable line number banner for each exec

      nagle                  Enable Nagle's congestion control algorithm

      old-slip-prompts       Allow old scripts to operate with slip/ppp

      pad                    Enable PAD commands

      password-encryption    Encrypt system passwords

      prompt                 Enable mode specific prompt

      pt-vty-logging         Log significant VTY-Async events

      sequence-numbers       Stamp logger messages with a sequence number

      slave-log              Enable log capability of slave IPs

      tcp-keepalives-in      Generate keepalives on idle incoming network connections

      tcp-keepalives-out     Generate keepalives on idle outgoing network connections

      tcp-small-servers      Enable small TCP servers (e.g., ECHO)

      telnet-zeroidle        Set TCP window 0 when connection is idle

      timestamps             Timestamp debug/log messages

      txacc-accounting       Enable transmit credit accounting

      udp-small-servers      Enable small UDP servers (e.g., ECHO)

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