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kill -9 `ps ux | grep netscape | awk '{ print $1 }'`; rm ~/.netscape/lock

Protecting yourself from being a spam base

Sendmail allows for someone to telnet to port 25 and do an expn (expand) to see what users and aliases are on your machine. Also, vrfy (verify) means someone can get legal e-mail addresses from your box and send spam through your machine.

Don't want that, so look in your /etc/sendmail.cf file for a line that looks like this:

###############
# Options #
###############

Now cut and paste these next few lines below that:

# turning off the expand option and requiring a helo from
# a remote computer
Opnoexpn,novrfy,needmailhelo

Now there is no expansion, no verify, and sendmail requires a helo with a legitimate DNS in order to use the mailer.

Then look in your /etc/mail/aliases file and ensure you have only your own boxen and/or subnet in there as OK or RELAY. That will help cut down on spammers' ability to find relay machines to do their dirty work for them.

Cleaning up Netscape crashes

You have a tip about Netscape leaving copies of itself running below, but you can make a general shell script to clean up a Netscape crash like this:

#!/bin/sh
#kill.netscape
killall -9 netscape
rm ~/.netscape/lock

Then all your users can use it and clean up the dreaded hundred instances of Netscape running when it crashed. Change netscape to netscape-communicator or netscape-navigator as appropriate.

Optimizing Netscape for Linux

Java in Netscape is unstable--turn it off.

Go to Edit then Preferences then Advanced

and make sure the Java and JavaScript buttons are not enabled. If you need it again, you can turn it back on by reversing the process. The button toggles on and off.

Another thing is that Netscape crashes easily and often, but many times when it crashes it leaves defunct copies of itself still running. To bring up the list of phantom Netscapes in a terminal use:

ps aux | more

Then you use kill -9 to kill all the processes that are still there but not doing anything so that Netscape will work right again. Many times a stale lock is left in the .netscape directory under your home directory as well, and it is a general nuisance. To get rid of the lock:

• just go to your home directory
• cd to .netscape
• ls to see that there is indeed a stale lock there
• and then use the command rm lock.

One last thing is that when there is a defunct copy of Netscape running in the background, many times a symptom is that links will not change colors after they have been visited--that feature of Netscape is to let you know you have viewed a webpage recently. Anyway, this is very irritating, and to get rid of it you have to kill defunct copies of Netscape as described above.

Thanks for your time, and I hope this is useful.