Ric Aleshire wrote: >> >> Both native- and sn1-branded zones will be capable of emulating hostids. >> However, lx-branded zones will forbid hostid emulation because supported >> Linux distributions (e.g., CentOS) retrieve hostids from /etc/hostid >> rather >> than kernel memory (as in Solaris OS). Zone administrators desiring >> to change >> an lx-branded zone's hostid can modify the zone's /etc/hostid file. >> >> Solaris 10 users will be able to configure a Solaris 8 or 9 >> container's hostid >> through the already-existing "add attr hostid" interface and new >> hostid property >> interface in zonecfg(1M). >> > > Can you clarify how this applies to other brands? It sounds like only > lx is specifically prohibited from using these > hostid interfaces. How about other brands, such as the cluster brand > and possible future native-based brands? > > -Ric
Ric, As long as sysinfo(SI_HW_SERIAL) system calls originating from within a branded zone are handled by the native Solaris kernel, the zone will be capable of emulating a hostid. All native-based brands will drop into the native kernel when sysinfo(SI_HW_SERIAL) system calls are made, so all native-based brands will be capable of emulating hostids. From what I have heard, cluster-branded zones are essentially native-branded zones with special callbacks, so cluster-branded zones will be capable of emulating hostids. Cluster-branded zones serve as an excellent example of the usefulness of non-global zone hostid emulation. Each cluster-branded zone could emulate a hostid. If clustering software migrates a cluster-branded zone between physical cluster nodes, then if the zone's configuration is preserved during the migration, then the zone's emulated hostid will be the same no matter which physical node hosts it. Without non-global zone hostid emulation, a cluster-branded zone's hostid can change when the zone migrates, potentially impacting how software within the zone will function. Regards, Jordan
