UNIX for Dummies Questions & Answers

have edit the /etc/hosts as belows

123.45.12.55 mypc

so when i do a who, i can see my "mypc" BUT after i changed, i cant see "mypc"

do i have to restart anything?

What did you change, there no reason to reboot for such a edit

Before we can really help, you need to post the OS version you are using. Thanks. Now to troubleshoot!

First, is mypc your actual host or a remote box? I am guessing that it is a remote WIN PC since you call it mypc or it is a linux box that is a PC.

Second, you are going will need to tell us why you changed it in the first place. Did you only have the IP address with NO hostname defined in /etc/hosts before? I know you said "so I can see it when I do a who command", but that seems like a strange reason to mess up your system?

Third, do you know the correct syntax for your OS version?

What did you get before when you typed a "uname -a"?

I would suggest changing it back to how it was before and always remember to make a backup copy of files that are system critical before editing them!!!

My guess is that he's either at a different PC, or uses DHCP - if your IP address changes, /etc/hosts doesn't know that...

1 )mypc is actual host or remote box?
>> actual host is the server which we telnet to? if yes, then mypc is a remote box. mypc is a pc which i am working from my desk to telnet to the actual host say myhost.

so from mypc, i type telnet myhost, then issue a who -uH, and saw the below

123.45.12.55 otherpc BUT

i have edit the /etc/hosts to

123.45.12.55 mypc

so i should see 123.45.12.55 mypc when i issue a who -uH instead of otherpc


2) oops, forget to inform u guys the os version, so after uname -a, i get the below

AIX myhost 3 4 <think this entry is the serial no>



TO livinfree

My guess is that he's either at a different PC, or uses DHCP - if your IP address changes, /etc/hosts doesn't know that...

1) i guess u are right that u said "he's at a different PC" on the assumption that i am doing a telnet to the host (so this is called remote?)

2) now, i dont have a single idea on this DHCP. there is no entry when i do a man DHCP so basically i dont understand the statement "your ip adderss changes, /etc/hosts doesnt know that"

If a name service, such as NIS or DNS, is being looked at first on the AIX system, before consulting /etc/hosts, then you will not see a change.

If your pc gets it's IP address via DHCP, then you might not have the same IP address after a reboot of the pc. DHCP assigns an IP address per request and once you shutdown the pc, DHCP can assign it to the next pc that request an IP.

yls177 , if u want to see changes after you reboot your machine , try ifconfig -a.
it will report you , your ethernet interface using , which serivce and I P address and netmask.