Specifications

Escala Tower PL & S, E, T System Hardware
Chapter 3: External Storage and SAN Subsystems 72/116
9es3s1c3.doc
Rev 5.9
02/12/2003
5.4.7. Multi Mode / Mono Mode Fibre Channel Director
The multi-mode Fibre Channel director is a single card that has two FC ANSI compliant 1-Gigabit
Fibre Channel interfaces for connection to open systems hosts and one high-speed path to cache. The
Fibre Channel director contains two advanced microprocessors that process commands and data from
the host and manage access to cache. The Fibre Channel SCSI protocol mapping and upper level
protocol layers are both implemented within the director. Each Fibre Channel director can support up
to 256 logical volumes per Symmetrix system. One physical interface is 52µ multi mode fiber and the
second one is 9µ mono-mode fiber.
5.4.8. 4-Port ESCON Director
The new ESCON and SRDF over ESCON channel directors use four processors providing the power
to drive four concurrent I/O operations. They provide more than two times the throughput of the older
ESCON and SRDF over ESCON channel directors, which use two processors and support two
concurrent I/O operations. The SRDF over ESCON channel director can support up to four individual
remote link connections for SRDF. Any remaining ports can be used for host connections. The
ESCON and SRDF over ESCON channel director requires Enginuity V5567.
5.4.9. ESCON Director
The ESCON director is a single card that offers four ports, which can support up to 1,024 logical
volumes per board. Symmetrix ESCON directors support 2 Control Unit Address (CUADD) images,
512 logical devices per ESCON port and 32 separate logical paths (LPaths) addressable to one port.
The 32 logical paths may be shared in any fashion between the 2 CU images. For example, all 32
logical paths can be configured on one CU image and none on the other. Alternatively, 32 logical paths
may be split between the ports (for example, 18 on CUADD 0 and 14 on CUADD 1)
5.4.10. SRDF Remote Link Director
The EMC Remote Link Director (RLD) facilitates the direct connection between two Symmetrix
systems in a Symmetrix Remote Data Facility (SRDF) or Symmetrix Data Migration Services (SDMS)
configuration. SRDF and SDMS implementations require a minimum of two, and support a maximum
of four, RLDs in each connected system. SRDF implementations can be either ESCON or Fibre
Channel. SDMS implementations are ESCON only.
For open systems, SRDF over Fibre Channel implementations use Remote Fibre Directors (RFD) for
connecting Symmetrix systems using high-speed Fibre Channel links. These directors are either multi-
mode fiber or multi/mono mode fiber and only one of the two ports is usable for the remote
connection.