HP StorageWorks Director and Edge Switch release notes (5697-8176, April 2009)

Devices in a mixed fabric may not login after power cycle if RD Zones are
configured
In a mixed fabric (containing both M-series and B-series switches) in McDATA Fabric interop mode,
devices will be prevented from logging in to a switch or director that is Power On Recycled (POR)
when RD Zones are configured. This is evident when the name server database is empty and the
F_Ports do not come online. To allow the devices to login, either execute cfgsave from a B-series
switch in the fabric, or delete the RD zones locally using the CLI.
A fabric initialization error may occur
A Fabric Init error may occur when a two-switch fabric has only one ISL between them, and the ISL
is blocked and unblocked. When this occurs, the fabric is not formed. This can be corrected by setting
one of the switches offline and then back online. This is disruptive to devices connected to the switch
that is set offline, and should be planned for accordingly.
Segmented ISL may be reported incorrectly in a mixed fabric
B-series switches display a Gx_ Port connection as Loopback (when they should display a segmented
condition) for M-series Edge Switch 2/24 or McDATA Sphereon 4500, M4700, or M4400. To avoid
this, configure the port as a G_Port and not a Gx_Port when attaching to a B-series switch.
Director and Edge Switch release notes 15