DNS turned on, FTP and telnet logins very slow

[Michael Hawthorne]

Ok, i turned on DNS on my A-Class machine, set the nsswitch.conf to look at /etc/hosts, then DNS. Everythings cool....

Except, now any telnet or ftp connections (from any machine not already in the /etc/hosts) get delayed at the login.

I realize that ftpd and telnetd are trying to lookup the IP of the incoming connection, then timing out.

How do I turn that off? So I can have DNS and yet have normal speed FTP and telnet logins.

---
Michael Hawthorne
mhawthorne@simpletel.com

[Alan Riggs]

I don't think you can, unless you are in control of the lokup behavior of the DNS server you have pointed to. If you are, then simply set DNS on that server to resolve locally or fail without cascading the query to other DNS servers. Otherwise, certain TCP protocols will always attempt name resolution and if you have DNS enabled you will have to wait for the DNS query to time out.

[Berlene Herren]

Is ypbind running? If so, try killing it and then telnet/ftp. Is that any faster?

Berlene

[Chris Collingwood]

Use SAM -> Networking and Communications -> Name Service Switch, and check that you only have /etc/hosts and then DNS set up. Make sure that the third (and possibly fourth on UX11) optional supplier (usually NIS/YP) is not set. Also check the "If information not found" and "If source is not configured" rollover is set to "Try next source" on /etc/hosts. I usually go through all the option on this menu screen and remove any reference to NIS, which is usually not configured, or is misconfigured.
Cheers

[Chris Collingwood]

Forgot to ask in my last response, if the incoming connections are from systems that are resolvable from DNS. If they are not, you would also see a long delay while your system grovelled into the DNS. Check that you can resolve the IP address and FQDN from DNS with nslookup.
Cheers

[Rita C Workman]

This drove me crazy...our DNS server is 'external', so I have no control of it or how it's setup. Our telnet connections in-house were taking what seemed forever. I found a couple docs that helped explain it to me, maybe they'll help you Doc ID A5338041 dtd 10.29.1998.
After you read it see if you come to the same conclusion . To me it said...either put the IP's in your host file or put them in your named.boot file. Or you chose to wait till DNS will return (in about 100 seconds) and give you a login prompt.

/rcw

[Michael F. Dick]

Hi,

I'd aggree with Chris on that one...try whether or not the hostnames of the client station are resolvable..2nd try whether your server can rech the dns server and the dns server can reach your server (might be a network problem somewhere).

Michael