After spending several days working on this problem I found
a solution. Installing ssh2 apparently causes some changes in
how the system authenticates the user logging in. During this time
I was configuring IP masquerading, a domain name server, and
mail, and also tried running ssh1. Many things were changing at once
over a short period of time.
1. One problem that developed was that a login at the console would
only work for operator. I changed /etc/pam.d/login from
auth required /lib/security/pam_securetty.so
auth required /lib/security/pam_pwdb.so shadow nullok
auth required /lib/security/pam_nologin.so
account required /lib/security/pam_pwdb.so
password required /lib/security/pam_cracklib.so
password required /lib/security/pam_pwdb.so nullok use_authtok md5 shadow
session required /lib/security/pam_pwdb.so
session optional /lib/security/pam_console.so
to
auth required /lib/security/pam_securetty.so
auth required /lib/security/pam_nologin.so
auth sufficient /lib/security/pam_pwdb.so shadow nullok
account required /lib/security/pam_pwdb.so
password required /lib/security/pam_cracklib.so
password required /lib/security/pam_pwdb.so nullok use_authtok md5 shadow
session required /lib/security/pam_pwdb.so
session optional /lib/security/pam_console.so
to fix this. Now any user can log in. Note that when making a change in this
file, you should reboot **two** times before evaluating the change. This
change also allowed telnet to start working again which I had still allowed
to run by purposely not commenting out its line in /etc/inetd.conf.
2. Even after logging in at the console, startx would now not work because of
an authentication failure. Changing /etc/inittab from Run Level 3 to Run Level
5 would get X window working when booting since gdm would automatically run.
Since I use two displays with different numbers of pixels and bit settings,
one possibility would be to introduce the lines
0=/usr/bin/X11/X -bpp 8 vt7
1=/usr/bin/X11/X -bpp 32 vt8
into /etc/X11/gdm/gdm.conf, where I had previously used Xconfigurator to set up
two displays of my desired sizes and bit depths. In this case, after booting,
the system would come up with the gdm login for 32 bits per pixel, but one could
enter ctrl Alt F7 to get the gdm login window for 8 bits per pixel. As it
turned out, the gdm 8-bit window causes the colors of various windows to change
as the mouse is moved around when running 8-bit applications. Since my main
reason for running this window is to use Enhanced SAOimage
(http://www.chara.gsu.edu/~gudehus/enhanced_saoimage.html) which is 8 bits, I
chose another approach. In gdm.conf I retained only the line
1=/usr/bin/X11/X -bpp 32 vt8. After booting and loggin on to the 32-bit window,
I enter ctrl Alt F1 to log on to the console, and then enter startx
(which now works because gdm has already run) to get the 8-bit window. My
.xinitrc file looks like:
#!/bin/csh
xrdb -load $HOME/.Xdefaults
xset c off s 240
sleep 2
xsetroot -solid blue
sleep 2
xload -display :0.0 -update 2 -g 150x80-135-0 &
sleep 2
xterm -ls -T ${HOST} -display :0.0 -cr red -g 80x24+0+0 -fg white -bg black &
sleep 2
exec fvwm -display :0.0
and the colors don't change as the mouse is moved. Note that all this applies
to Redhat 6.0. I don't know about other versions.
Donald
> Hello,
> I am running Redhat 6.0 and set up IP masquerdaing and a domain name
> server. When I tried to set up mail I ran into some problems, and
> now I can't log on to my system. However I can log in over the local
> network and over the internet. The file /var/log/messages shows
> "login failure from null" when I try to log in at the computer. I
> have looked at several of the setup files but don't see anything
> different from before. Suggestions will be appreciated.
> Donald
> ******************************************************************************
> Donald H. Gudehus
> Remove (.nospam.) and whitespace when responding.
> Web page: http://www.chara.gsu.edu/~gudehus/
by