Using a Laptop on the Mountain

Connecting your laptop to the net is a simple matter of assuming a new identity. To do so, you will need a laptop with a working ethernet interface and a 10BaseT connector. You will also need root access to your machine.

Each telescope has assigned to it several identities for this purpose, listed in the following table.  Note the non-standard value for the 3rd number in the subnet mask at the 61".
90" Telescope name IP
subnet mask bokpcx
gateway bokpcy

61" Telescope name IP
subnet mask bigpcx
gateway bigpcy


First, pick a machine name. Make sure that this identity is not already taken by another machine. To be sure that it is free, try pinging that machine from a machine already connected to the net (such as the data-taking computer). For example,

If you get no response, it is a good bet that your choice is available.

Once you have selected an identity, you must make your laptop adopt it. Before you do this, however, make sure that you know all of the data necessary to restore your machine to its original state. If it is normally directly connected to a network, you will need to know the same items that are listed in the table above. If it is not e.g., you normally connect remotely via an ISP), you will need to be sure of how your machine is currently set up. DO NOT NEGLECT THIS STEP, for you will have to relinquish your machine's new identity when you leave the mountain!  The best way to keep this data is to write down the value of everything you replace in the instructions below.

Now that you have all the data you need (and the data you will need later to undo this procedure), you can begin the change. Begin by connecting your ethernet cable to one of the 10BaseT ports above the rear of the counter. Then continue with the section appropriate for the operating system you are running.

Connecting a Linux PC

This section describes how to connect a Linux PC based upon the RedHat 6.1 release. It is similar to many other distributions, but beware: if you are not running RH6.1 you may be on your own.

There are several configuration utilities available for Linux. As of this writing, the fanciest, linuxconf, does not seem sufficiently stable for us to recommend its use. The older netcfg seems to work well, however. In the following we will describe the process using netcfg. Even if you are currently using linuxconf for configuration, you can still use netcfg without any conflict.

First become root and then type netcfg; a window will appear. If it is not already highlighted, click on the ``Names'' button. Enter the new hostname in the space provided after ``Hostname:''. Enter ``'' after ``Domain:''. Enter the nameserver (DNS) entries from the table above as the first entries in the ``Nameservers:'' list. If you are from Steward, you probably already have the DNS entries listed.

Next click on the ``Hosts'' button. Click on ``Add''; a window will pop up, into which you will enter the new hostname and its IP number in the spaces provided. Enter the fully-qualified name (e.g. after ``Name:'', and the simple hostname (e.g. bokpcz) after ``Nicknames:''.

Next click on ``Interfaces''. Double-click on the ethernet interface. Enter the new IP number after ``IP:'' and the new subnet mask after ``Netmask:''. Make sure that ``Interface configuration protocol:'' reads ``none'', and click ``done''.

Finally, click on the ``Routing'' button. Enter the gateway address after ``Gateway:''.

Now click ``Save'' at the bottom of the panel, and click ``Quit''.

Reboot your machine (shutdown -h now or reboot), and it should have the new identity. To revert to your original configuration, merely follow the same steps with your original data.

Connecting a Windows 95/98 PC

First choose ``Start/Settings/Control-panel'' from the start icon. Click on the ``Network'' icon in the control panel.

In the window which appears, scroll down under ``Configuration'' and double-click on the line which says ``TCP/IP > (your ethernet adaptor brand)''. The ethernet configuration panel will pop up.

In this window, first choose the ``IP Address'' flag at the top. Click on the ``Specify an IP address'' button, then enter the IP number and subnet mask in the fields provided.

Next choose the ``WINS Configuration'' flag at the top. Click on the ``Disable WINS Resolution'' button.

Next choose the ``Gateway'' flag at the top. Delete any old data (by highlighting it and clicking ``Remove''). Now enter the new gateway address in the space provided and click ``Add''.

Choose the ``DNS Configuration'' flag at the top. Click the ``Enable DNS'' button, then put in the new hostname after ``Host:'' and put in'' after ``Domain:''. Type in the new DNS server IP in the space provided and click ``Add''.

Choose the Bindings tag at the top. Turn off everything but ``Client for Microsoft Networking''.

Finally, click on OK at the bottom. When the machine asks if you wish to reboot, click on ``Yes''.

Again, to reset your machine to its original configuration, follow this procedure with the data you removed.


To print at the 90" on printer lw8 (in the control room), send print jobs to machine lw8host with queue name lw8. At the 61", use lw17 on lw17host with queue name lw17. In what follows we will assume lw8 on Kitt Peak.

Under Linux, use printtool.  Become superuser and type printtool. In response to the printer type dialog, choose ``Remote Unix (lpq) Queue'' and click ``OK''. Next fill in at least the remote host (lw8host) and remote queue (lw8) lines. You might want to call the queue lw8 on your laptop to avoid confusion: put ``lw8'' in the box after ``Names'' at the top. Next click on ``Select'' after ``Input Filter'', and choose ``PostScript printer'' from the list. (Do NOT choose any of the HP printer models even though lw8 is an HP printer; these are for non-postscript versions.) Set the resolution to ``600x600'' and click ``OK'' on the filter panel and then ``OK'' on the remote queue panel. You can test the connection by clicking on the entry you just made in the printtool main window and then choosing ``Print PostScript test page'' from the ``Tests'' menu.

Windows users can make use of the utility QVT/lpr (available from Setup is straightforward, using as the host and lw8 as the queue.

Phil Pinto, Gary Schmidt, Alan Koski