[hercules-390] No multicast support for LCS?

[[e-mail] [hercules-390]]

I'm trying to get OSPF to run on z/OS under Hyperion on Windows 7. OSPF does not see my router as a neighbor, but the router sees z/OS as a neighbor. After much research, I finally did a packet trace on the z/OS TCP/IP stack and I can see multicast packets (hello packets) being sent and received. However when I do a packet trace of the OSPF component, I only see multicast packets being sent, none received. I found an old z/OS APAR that sheds some light on the issue, even though it does not apply to my situation. It appears there is a query, QIPAsst, that determines if an LCS interface is capable of multicast. If the response is not positive, multicast packets received on the interface are discarded. I appears that the Hercules LCS implementation does not support QIPAsst. Looks like I won't be using OSPF unless/until that is resolved.

Here is the APAR information: http://www-01.ibm.com/support/docview.wss?uid=swg1PK55520 http://www-01.ibm.com/support/docview.wss?uid=swg1PK55520

[Ivan Warren [e-mail] [hercules-390]]

Post by ***@execpc.com [hercules-390]
I'm trying to get OSPF to run on z/OS under Hyperion on Windows 7.
OSPF does not see my router as a neighbor, but the router sees z/OS as
a neighbor. After much research, I finally did a packet trace on the
z/OS TCP/IP stack and I can see multicast packets (hello packets)
being sent and received. However when I do a packet trace of the OSPF
component, I only see multicast packets being sent, none received. I
found an old z/OS APAR that sheds some light on the issue, even though
it does not apply to my situation. It appears there is a query,
QIPAsst, that determines if an LCS interface is capable of multicast.
If the response is not positive, multicast packets received on the
interface are discarded. I appears that the Hercules LCS
implementation does not support QIPAsst. Looks like I won't be using
OSPF unless/until that is resolved.
http://www-01.ibm.com/support/docview.wss?uid=swg1PK55520
<http://www-01%0A%20.ibm.com/support/docview.wss?uid=swg1PK55520>

I suggest you open a GITHUB issue for this.

I cannot promise we have enough information to see how to implement
Multicast MAC address registration to an LCS instance (or if LCS should
let any multicast frames pass), but it's worth opening the issue so it
can be tracked.

--Ivan


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