telnet 0

[Shahril M]

Hi,

This command opens a new session to the current host. However, I have ever encountered boxes which do not recognise the 0 (zero) parameter.

Can someone share with me where this is configured?


Rgds,
Shahril

[harry d brown jr]

What kind of boxes would that be? Could you tell us the OS, patch level, bit level, hareware model? Security settings? applications?

live free or die
harry

[Wodisch]

Hi,

I used to use "telnet ." on HPUX10.20 and 11.0, but it seems to not work any more on HPUX11i :-(
...and not on S(l)olaris 7/8 and not on linux...

FWIW,
Wodisch

[John Palmer]

It's down to the way that IP name resolution has been implemented, I doubt very much that you'd be able to configure it.

If you try ping 0 or . or .. or ... you'll see a response from 127.0.0.1 the loopback address.

Personally, I wouldn't worry about it - if typing 'telnet localhost' is too much trouble, add a single character hostname as an alias to localhost and use that.

Regards,
John

[Deshpande Prashant]

Hi
Recently I have upgraded couple of my boxes to 11i from 11.0 to find telnet 0 won't work on 11i.

Thanks
Prashant.

[Scott Van Kalken]

I'm not 100% sure (so essentially what I'm saying is that this is pure speculation)

but I should think that the implementation of route.h may have changed.

[Kellogg Unix Team]

Prashant,

We have 11i servers and 'telnet 0' works just fine. We did a fresh install on them.

sysA # uname -a
HP-UX sysA B.11.11 U 9000/800 142575636 unlimited-user license
sysA # telnet 0
Trying...
Connected to 0.
Escape character is '^]'.
Local flow control on
Telnet TERMINAL-SPEED option ON

HP-UX sysA B.11.11 U 9000/800 (te)

login:

...Manjeet

[Kellogg Unix Team]

Shahril,

How does your /etc/hosts look like? Does it have an entry for localhost?

Also, are you making use of /var/adm/inetd.sec file? If yes, can you post telnet-related entries?

Rgds
...Manjeet

[Shahril M]

Hi John,

I just want to learn how it is configured.

Hi Manjeet,

My /etc/hosts is normal:
127.0.0.1 localhost loopback
followed by the various machine entries

And, no, I am not using inetd.sec.


Rgds,
Shahril

[Kellogg Unix Team]

Shahril,

Looking at the responses so far (and checking for 11i myself), I don't see problem to be an OS limitation. When you say you are unable to "telnet 0" for some servers, were you -

1. able to do "telnet localhost" successfully?
2. ping 0 (as suggested by John) successfully?
3. telnet to the server (as opposed to remsh)?

I vaguely remember seeing this problem somewhere. If you can post more details viz. under what circumstances you see this problem, that will help.

Rgds
...Manjeet