On Thursday, 03/16/2006 at 05:49 EST, "Hughes, Jim - OIT" 
<[EMAIL PROTECTED]> wrote:
> We are running ZVM 3.1 and TCP/IP 3A0.
> 
> We use VMFTP quite heavily here. We have a modification to VMFTP named
> NODELAY. This NODELAY fix changes the original start up command from
> "FTP 0" to FTP 0.0.0.0"
> 
> If I issue a regular FTP command with no arguments, I get prompted
> straight off to enter the address of the FTP server. No delay at all.
> 
> If I enter the command FTP 0.0.0.0, there is a delay followed by a
> message "unknown host:".
> 
> Perhaps I am just slow because after 2 years of ZVM and TCPIP 3A0
> running in production, I noticed tonight all the VMFTP commands have
> about a 3-6 second delay before anything inside the VMFTP macro. I
> suspect its because FTP is locating the ftp server at 0.0.0.0.
> 
> Have any of you noticed this behavior too?
> 
> If so, how did you get around the delay when looking for 0.0.0.0???
> 
> Thanks in advance.
> 
> Please make me look stupid and tell me it's a tcpip configuration
> option. It would make my day.

The excessive delay with "FTP 0" was seen when the name server config in 
TCPIP DATA was bad or there was a routing loop in the network.  The delay 
was RESOLVERTIMEOUT x RESOLVERRETRIES x the number of bad NSINTERADDR 
entries.

Turn on TRACE RESOLVER in TCPIP DATA and use TRACE option on the FTP 
command to get a full picture of what's happening.  Here's what I see with 
TRACE (but no resolver trace):
 
16:26:17 ftp 0.0.0.0 (trace exit 
16:26:17 VM TCP/IP FTP Level 520 
16:26:17 Translate Table: STANDARD 
16:26:17 about to call BeginTcpIp 
16:26:17 Connecting to 0.0.0.0, port 21 
16:26:17 SysAct 0 21 0 CC -1 
16:26:17 ==> Active open to host 0.0.0.0 port 21 from host 0 port 65535
16:26:17 TcpOpen error: unspecified foreign address in active open 
16:26:17 Unable to connect to 0.0.0.0 
16:26:17 TcpOpen error: unspecified foreign address in active open 
16:26:17 SysHalt has been Called 
16:26:17 Ready(10000); T=0.01/0.02 16:26:17 

Alan Altmark
z/VM Development
IBM Endicott

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