Please Whitelist This Site?

I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free. And I have a family to support, just like you. :)

If you like The TCP/IP Guide, please consider the download version. It's priced very economically and you can read all of it in a convenient format without ads.

If you want to use this site for free, I'd be grateful if you could add the site to the whitelist for Adblock. To do so, just open the Adblock menu and select "Disable on tcpipguide.com". Or go to the Tools menu and select "Adblock Plus Preferences...". Then click "Add Filter..." at the bottom, and add this string: "@@||tcpipguide.com^$document". Then just click OK.

Thanks for your understanding!

Sincerely, Charles Kozierok
Author and Publisher, The TCP/IP Guide


NOTE: Using software to mass-download the site degrades the server and is prohibited.
If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.

The Book is Here... and Now On Sale!

The whole site in one document for easy reference!
The TCP/IP Guide

Custom Search







Table Of Contents  The TCP/IP Guide
 9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)
      9  TCP/IP Key Applications and Application Protocols
           9  TCP/IP Interactive and Remote Application Protocols
                9  Berkeley Remote ("r") Commands

Previous Topic/Section
Berkeley Remote Shell (rsh)
Previous Page
Pages in Current Topic/Section
1
Next Page
Internet Relay Chat Protocol (IRC)
Next Topic/Section

Other Berkeley Remote ("r") Commands (rcp, ruptime, rwho)

The rlogin and rsh commands are the generic members of the Berkeley “r” family of programs that allow remote access to a host. To complement these, a small number of specific remote commands were also defined. These are essentially remote versions of some of the more common UNIX functions—instead of the command being applied to only one system, however, it is used between two systems or across all systems on a TCP/IP network.

All of these commands are based on rlogin the same way that rsh is. They work in the same way, but instead of opening up a session or passing a user-specified command to the remote host, they execute a particular function. The following are the most common of these remote commands and briefly, how each is used:

  • Remote Copy (rcp): This is the remote version of the UNIX copy (cp) command; it allows a file to be copied between the local host and the remote host, or between two remote hosts. The usual syntax is basically the same as the regular cp command, but the source and/or destination is specified as being on a remote host.

    The rcp command can be used in a manner similar to
    FTP, but is much simpler and less capable. Or to put it another way: rcp is to FTP, what rlogin is to Telnet. (That’s not a perfect analogy, but it’s pretty close.)

  • Remote Uptime (ruptime): The UNIX command uptime is used to display how long a computer has been running since it was last booted, along with information related to its current load. ruptime is the remote version of this command; it displays the current status of each machine on the network (up or down), how long each up machine has been up since its last boot, and its load statistics.

  • Remote Who (rwho): This is the remote version of the who command. Where who shows all the users logged on to the host where it is run, rwho shows all users logged on to all machines on the network.

The ruptime and rwho commands both rely on the presence of the rwhod (remote who daemon) running in the background on networked machines. These processes routinely share information with each other about host uptime and who is logged on to each system, so it can be quickly displayed when either ruptime or rwho is run.

On some operating systems, other remote commands may also be implemented. As with rlogin and rsh, security issues may apply to these commands, and there may be efficiency concerns with others (such as rwho). For these reasons, on many networks these commands are no longer used.

 


Previous Topic/Section
Berkeley Remote Shell (rsh)
Previous Page
Pages in Current Topic/Section
1
Next Page
Internet Relay Chat Protocol (IRC)
Next Topic/Section

If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider purchasing a download license of The TCP/IP Guide. Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

The TCP/IP Guide (http://www.TCPIPGuide.com)
Version 3.0 - Version Date: September 20, 2005

© Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.