User manual

Microsoft Windows™
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Thus even though host OS and VAX MP share the network card, they will be both sending and receiving
Ethernet packets to/from the wire as two different machines.
Using TCP/IP Services for OpenVMS, adapters in the above example will be bound IP addresses the
following way, for XQA and XQB correspondingly:
$ TCPIP SET INTERFACE QE0 /HOST=192.168.1.200
$ TCPIP SET CONFIGURATION INTERFACE QE0 /HOST=192.168.1.200
$ TCPIP SET INTERFACE QE1 /HOST=192.168.3.200
$ TCPIP SET CONFIGURATION INTERFACE QE1 /HOST=192.168.3.200
Depending on exact value of network addresses being used and network topology it may be necessary
to additionally specify options
/NETWORK_MASK=x.y.z.w and /BROADCAST_MASK=m.m.m.m.
(Bridged set-up)
It is possible to bridge host NIC and MS Loopback interfaces in order to eliminate dual network
addressing per VAX MP instance and instead have only one IP address for host machine and only IP
address for VAX instance. There is little benefit in bridged set-up under Windows since Windows
supports single-interface setup that provides all the benefits of bridged set-up at a simpler
configuration.
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Nevertheless technically bridged set-up is possible under Windows.
Bridging can be easily performed with standard Windows interface bridging facility. In a bridged set-up
VAX MP will be using only MS Loopback Adapter bound typically to XQ and bridged in Windows to host
NIC.
To create a bridge on Windows XP, open Control Panel’s section Network Connections, right-click on MS
Loopback Adaptor and select “Add to Bridge”, then do the same with Ethernet adapter. Then right-click
on “Network Bridge” interface and configure it as desired. You can add interfaces to the bridge and
remove interfaces from the bridge via Network Bridge properties dialog.
To create a bridge on Windows 7, open Control Panel’s section Change Adapters Settings, select
adapters to be bridged, right-click on any of selected adapters and select “Bridge Connections”.
Once the bridge is created, you need to configure VAX instance with only single XQ adaptor attached to
MS Loopback Adaptor and utilizing single IP address for VAX instance. XQB does not need to be enabled
in VAX MP bridged configuration script or attached to any host interface.
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Bridged set-up would have offered benefits beyond a single-interface set-up in case of Gigabit Ethernet NICs if
Windows bridging performed translation of jumbo frames to regular-sized frames. At this time we are not aware
whether it does.