Hi,

I am installing some SAP software on a couple of HP-UX v11.11
servers.

As part of this installation (EP6.0 Web Dispatcher, for those
familiar with SAP), I need to specify a port for communication
between the two HP-UX servers. There is no firewall or anything
else (To the best of my knowledge) hindering communication
between the servers.

I chose port 8081 (SAP's suggested default), but the functionality
did not work. SAP's logs indicated communication issues between
the two HP-UX servers.

I tried other port numbers, but the same issue occured.

In the SAP documentation, they suggest trying (From host1)
'telnet <host2> <port>' to check whether the port is
valid.

I tried 5 or 6 ports, but telnet always failed with the
message 'telnet: Unable to connect to remote host: Connection
refused'. Yet, the command 'telnet <host2>' works.

Where can I get more information as to which ports may be
valid for communication between the servers? I checked
'netstat' and '/etc/services', but I am having a hard time
determining this.


Thanks,
BASIS Consultant

basis_consultant@hotmail.com wrote:
> I am installing some SAP software on a couple of HP-UX v11.11
> servers.

> As part of this installation (EP6.0 Web Dispatcher, for those
> familiar with SAP), I need to specify a port for communication
> between the two HP-UX servers. There is no firewall or anything
> else (To the best of my knowledge) hindering communication
> between the servers.

> I chose port 8081 (SAP's suggested default), but the functionality
> did not work. SAP's logs indicated communication issues between
> the two HP-UX servers.

> I tried other port numbers, but the same issue occured.

> In the SAP documentation, they suggest trying (From host1)
> 'telnet <host2> <port>' to check whether the port is
> valid.

> I tried 5 or 6 ports, but telnet always failed with the
> message 'telnet: Unable to connect to remote host: Connection
> refused'. Yet, the command 'telnet <host2>' works.

Unless there is a TCP endpoint in the LISTEN state (netstat -an) on
the remote system, where the endpoint is bound to the <port> value to
which you are trying to connect, the error message you get from telnet
is expected.

So, check netstat -an | grep LISTEN on the remote system first.

Did you start the SAP software on the remote side?

rick jones
-- 
a wide gulf separates "what if" from "if only"
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

Hi Rick,

Thanks for the response. I made a mistake in the original
description; The problem is not the communication between the
servers, but that the server containing the Web Dispatcher
cannot access a port needed for the functionality to work:

[Thr 6] *** WARNING => Connection request from (0/0/0) to host:
 <hostname>, service: 8881 failed (NIECONN_REFUSED)
{00010002} [icxxconn_mt.c 2123].

Thus, it seems like the issue is that the SAP configuration
expects HP-UX to use a specific port number (Mentioned in
an SAP config file) and that HPUX cannot use that port.

Port does not show up on 'netstat -an'.

Thanks,
BASIS Consultant

Rick Jones wrote:
> basis_consultant@hotmail.com wrote:
> > I am installing some SAP software on a couple of HP-UX v11.11
> > servers.
>
> > As part of this installation (EP6.0 Web Dispatcher, for those
> > familiar with SAP), I need to specify a port for communication
> > between the two HP-UX servers. There is no firewall or anything
> > else (To the best of my knowledge) hindering communication
> > between the servers.
>
> > I chose port 8081 (SAP's suggested default), but the functionality
> > did not work. SAP's logs indicated communication issues between
> > the two HP-UX servers.
>
> > I tried other port numbers, but the same issue occured.
>
> > In the SAP documentation, they suggest trying (From host1)
> > 'telnet <host2> <port>' to check whether the port is
> > valid.
>
> > I tried 5 or 6 ports, but telnet always failed with the
> > message 'telnet: Unable to connect to remote host: Connection
> > refused'. Yet, the command 'telnet <host2>' works.
>
> Unless there is a TCP endpoint in the LISTEN state (netstat -an) on
> the remote system, where the endpoint is bound to the <port> value to
> which you are trying to connect, the error message you get from telnet
> is expected.
>
> So, check netstat -an | grep LISTEN on the remote system first.
>
> Did you start the SAP software on the remote side?
>
> rick jones
> --
> a wide gulf separates "what if" from "if only"
> these opinions are mine, all mine; HP might not want them anyway... :)
> feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

basis_consultant@hotmail.com wrote:
> Hi Rick,
> 
> Thanks for the response. I made a mistake in the original
> description; The problem is not the communication between the
> servers, but that the server containing the Web Dispatcher
> cannot access a port needed for the functionality to work:
> 
> [Thr 6] *** WARNING => Connection request from (0/0/0) to host:
>  <hostname>, service: 8881 failed (NIECONN_REFUSED)
> {00010002} [icxxconn_mt.c 2123].
> 
> Thus, it seems like the issue is that the SAP configuration
> expects HP-UX to use a specific port number (Mentioned in
> an SAP config file) and that HPUX cannot use that port.
> 
> Port does not show up on 'netstat -an'.
> 
> Thanks,
> BASIS Consultant
> 
> Rick Jones wrote:
> 
>>basis_consultant@hotmail.com wrote:
>>
>>>I am installing some SAP software on a couple of HP-UX v11.11
>>>servers.
>>
>>>As part of this installation (EP6.0 Web Dispatcher, for those
>>>familiar with SAP), I need to specify a port for communication
>>>between the two HP-UX servers. There is no firewall or anything
>>>else (To the best of my knowledge) hindering communication
>>>between the servers.
>>
>>>I chose port 8081 (SAP's suggested default), but the functionality
>>>did not work. SAP's logs indicated communication issues between
>>>the two HP-UX servers.
>>
>>>I tried other port numbers, but the same issue occured.
>>
>>>In the SAP documentation, they suggest trying (From host1)
>>>'telnet <host2> <port>' to check whether the port is
>>>valid.
>>
>>>I tried 5 or 6 ports, but telnet always failed with the
>>>message 'telnet: Unable to connect to remote host: Connection
>>>refused'. Yet, the command 'telnet <host2>' works.
>>
>>Unless there is a TCP endpoint in the LISTEN state (netstat -an) on
>>the remote system, where the endpoint is bound to the <port> value to
>>which you are trying to connect, the error message you get from telnet
>>is expected.
>>
>>So, check netstat -an | grep LISTEN on the remote system first.
>>
>>Did you start the SAP software on the remote side?
>>
>>rick jones
>>--
>>a wide gulf separates "what if" from "if only"
>>these opinions are mine, all mine; HP might not want them anyway... :)
>>feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
> 
> 
Is the port number/UDP-TCP defined in the /etc/services file? And 
perhaps it also need to be defined in /etc/inetd.conf as the application 
that needs to run when the port is opened ( I'm not familiar w/ SAP )

basis_consultant@hotmail.com wrote:
> Hi Rick,

> Thanks for the response. I made a mistake in the original
> description; The problem is not the communication between the
> servers, but that the server containing the Web Dispatcher cannot
> access a port needed for the functionality to work:

> [Thr 6] *** WARNING => Connection request from (0/0/0) to host:
>  <hostname>, service: 8881 failed (NIECONN_REFUSED)
> {00010002} [icxxconn_mt.c 2123].

> Thus, it seems like the issue is that the SAP configuration expects
> HP-UX to use a specific port number (Mentioned in an SAP config
> file) and that HPUX cannot use that port.

> Port does not show up on 'netstat -an'.

If the port does not show-up in netstat -an output then either the
thing that was supposed to create a listen endpoint on that port is
not running, or its attempts to create the listen endpoint failed.

One one machine, or the other, start a tcpdump trace with the snaplen
set to oh 128 bytes.  Feel free to use a filter expression for just
that port number:

tcpdump -i <interface> -s 128 -w /tmp/trace.raw

then try the connection, then stop the tcpdump trace and process it:

tcpdump -r /tmp/trace.raw -x (or -X) Find the TCP SYNchronize segment
- it will be the one with the 'S' flag set.  You should then see a TCP
ReSeT segment ('R') in response.  Working backwards from the last of
the hex output for that segment, find the corresponding ASCII
character (man ascii) and you will get the error message that HP-UX
puts into its RST segments by default.  I suspect it will say
something like "no listener" or somesuch.

rick jones
-- 
portable adj, code that compiles under more than one compiler
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...