On Wednesday, 09/21/2011 at 12:55 EDT, David Boyes <[email protected]> wrote: > > Rsh on an internal z/VM virtual network achieves both. Things like Live Guest > > Relocation introduces an anomaly into the equation, since a what appears as > > "internal" one moment may in fact be "remote" at the next. > > ??? Shouldn't the topology not change? Other than physical host changes, I've > been assuming the LGR stuff effectively is a unit black box from external hosts.
Topology doesn't change, but traffic flow does. If two virtual servers are using the same VSWITCH on System A, they communicate directly, without external bridging. If one of them relocates to System B, then the guests virtual NICs will be reconnected to a VSWITCH on System B. Even though the two VSWITCHes have the same name, they may be using different OSAs (e.g. on different CECs). Once they are on different OSAs, then traffic will leave the box. Now, since we're talking about a shared L2 network, the exposure of the traffic between the two guest will be limited to sniffers on the local set of trunked switches. But for many installations, leaving the box is the encryption trigger. If the two VSWITCHes share an OSA, isolation mode is not permitted (shared L2), so the traffic will short circuit in the OSA to the other VSWITCH. > It is kinda surprising that VM and MVS still ship with plaintext tn3270 as the > default. > > Sounds like a requirement. As long as you don't mind the system having a default self-signed certificate, it's feasible. Alan Altmark Senior Managing z/VM and Linux Consultant IBM System Lab Services and Training ibm.com/systems/services/labservices office: 607.429.3323 mobile; 607.321.7556 [email protected] IBM Endicott ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
