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>From: Mai Nguyen <address@hidden> >Organization: National Center for Hydro-Meteorological Forecasting of Vietnam >Keywords: 200312020023.hB20N4p2027742 IDD LDM Linux Mai, >Thanks for your supports. No worries. We are glad to help when we can. >These are the most that I can remember. > >+ I checked very carefully with the IPs. They seem ok. >But the ethernet never activates itself after >rebooting. So normally I have to go into Network in >System setting to activate the connections. That was >the reason why you couldn't log on my computer >yesterday, since my workmate rebooted the computer >before he has gone home without checking the >connection. So, the automatic start of networking at boot time was not setup/setup correctly. >+ I came to Authentication option. Changed the option >to use Keberoos (something like that), there >have been some parameters in the textboxes. I think I >wiped them clear. I've done that because when logged >in from other computer, I always got the message >something like: "the KDS (or KDC) can't recognize >..initial credentials " We are wondering why you chose to turn on Kerberos? We do not use it here, so our experience with it is minimal. >+ Changed Security to medium (from NO FIREWALL) >Nothing happened immediately until I reboot again. Kerberos and changing the firewall may be the cause of your problems. >Hope tomorow will be a better day. Yes. Here is what to do (you need to be at the computer to do these steps): 1) reboot 2) it is likely that you are using the 'grub' OS loader. If yes, you should be looking at a screen that gives you one or more options for starting Linux. If you read the text shown on this screen, it should say that you can press 'e' to edit boot-up options. Press 'e' before the system continues booting on its own (there is a count down of 10 seconds and then booting will continue unless you hit certain keys like 'e') 3) you should next be looking at a list of options for boot. The first option should begin with 'root', and the second will begin with 'kernel' and followed by kernel options. There may be a third line, a fourth, etc. Linux allows you to keep more than one kernel on the disk and select which one you want to boot from. Use the down arrow key to select the first 'kernel' in the list (not the line that begins with 'root') and hit the 'Enter' key. 4) you will now be looking at a long line of stuff related to booting the first kernel in the list from 3). You want to type: <space> single That is a single space followed by 'single', then press the 'Enter' key. You will then be looking at the same screen that you were at the beginning of 3). You can either wait for booting to continue after 10 seconds, or press 'b'. At this point, the machine will begin booting. Instead of coming up into multi-user mode, however, it should stop at a command line prompt and wait for your input. At this point you will be doing things as 'root'. Here is what you do: 5) rename the firewall configuration file: mv /etc/sysconfig/iptables /etc/sysconfig/iptables- 6) edit the /etc/nsswitch.conf file and change the line that begins with 'passwd' so that it looks like: passwd: files nisplus At this point, you should be able to let the machine continue booting into multi-user mode: 7) type 'exit' at the command line prompt If all goes as we think it should, the system should come up with the login screen you are used to, and you should be able to login as 'root'. If there really was a problem logging in as the user 'ldm' -- meaning that the password isn't accepted --, then you can set the password for 'ldm'. Before logging in as 'root', however, I would check to see if you can login as 'ldm' or 'nawips'. After you have the 'ldm' login working again, you should pay attention to why networking is not being automatically started on reboot. Please do not turn on Kerberos or the firewall just yet. >Bye for now Tom Please let us know the results of the above. Cheers, Tom -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publically available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.