This weekend I upgraded from z/VM 4.4.0 to 5.2.0 and ran into an 
unexpected problem with connectivity through vswitches to the external 

network.  I'm trying to figure out if the problem is in my vswitch 
definitions or if it's a reportable issue.

At the moment it appears that private IP address ranges (eg 
192.168.xxx.xxx, 10.xxx.xxx.xxx, 172.16.64.xxx) which worked fine through
 
a vswitch in 4.4.0 do not work at all through a vswitch on 5.2.0.

Private IP addresses in the same subnet, on the same VLAN, on the same 

vswitch couldn't ping each other or their external gateway.  The public I
P 
addresses on the same vswitch had no trouble pinging their external 
gateway.  Private IP addresses with direct OSA conections had no problems
 
either.

I was able to confirm it was a vswitch related problem through testing 

with my z/VM TCPIP stack.  Normally it has a dedicated OSA connection and
 
a private IP address of 172.16.64.3 on VLAN 7.  On zVM 5.2 I was able to 

PING its external gateway at 172.16.64.1.  When I changed the TCPIP stack
s 
network connection from a dedicated OSA to a virtual NIC on the vswitch 

the ping failed.

My vswitch was defined in z/VM 4.4.0 with:

     DEFINE VSWITCH SWITCH02 RDEV 0500 F804 PORTNAME PT0500 PTF804

and in 5.2.0 with:

     DEFINE VSWITCH SWITCH02 RDEV 0500 F804 VLAN 7 PORTNAME PT0500 PTF804


For testing the TCPIP NIC on the vswitch it was authorized with:

     SET VSWITCH SWITCH02 GRANT TCPIP    VLAN 7

In both cases, PROFILE TCPIP includes:

     LINK ETH0 QDIOETHERNET [EMAIL PROTECTED] VLAN 7


Changing TCPIP's GRANT to include PORTTYPE TRUNK, and verifying the chang
e 
with Q VSWITCH ALL DETAILS, had no effect.

On the exact same switch, SWITCH02, other Linux guests on VLAN 2 with 
public IP addresses (eg 164.165.57.xxx) had no trouble communicating with
 
the network outside the z/890.  They are authorized to the vswitch with:

    SET VSWITCH SWITCH02 GRANT <userid> VLAN 2

The problem also manifested itself on the other vswitch carrying traffic 

on private IP addresses for other VLANs (3 and 4).


Is there something I've overlooked in the changes to vswitches from 4.4.0
 
to 5.2.0?  Or is this a reportable problem?

Brian Nielsen

P.S. The problem has been temporariliy circumvented by connecting the 
userids with priviate IP address on VLAN 7 to a guest LAN and using the 

zVM TCPIP stack to route their traffic to the OSA.  (Yuck, but it works.)

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