Specifications

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Cisco SN 5428-2 Storage Router Software Configuration Guide
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Chapter 1 Before Configuring SN 5428-2 Storage Router Software
FCIP Overview
Once configured, FCIP instances on each storage router become active and establish their connectivity
via the IP network. The storage devices in one SAN access the storage devices in the connected SAN
using FC frames, which are encapsulated in IP packets by the FCIP instance running in the SN 5428-2,
and transmitted to the peer SN 5428-2. The peer FCIP instance strips the IP packet data and passes only
the FC frames over the FC interfaces to the storage devices.
The peer SN 5428-2 Storage Routers deployed for FCIP must be configured to use the same protocol:
TCP or raw. TCP protocol uses standard TCP flow control and error recovery algorithms. Raw protocol
uses a proprietary connection protocol, but provides more operational control over flow control and error
recovery than standard TCP/IP.
If the selected protocol is TCP, one FCIP instance must be configured as the TCP client; the other FCIP
instance must be configured as the TCP server. The only difference between FCIP instances configured
as TCP client and TCP server is which FCIP instance initiates the connection: the TCP client initiates
the connection.
FCIP transports FC frames between SANs by performing the following actions (Figure 1-15):
• Transporting FC frames between a SAN and an SN 5428-2 that is deployed for FCIP
• Encapsulating FC frames in IP packets and transporting the IP packets to a peer SN 5428-2 that is
deployed for FCIP
• Receiving IP packets and transporting as FC frames between the peer SN 5428-2 and a connected
SAN
Note that FC traffic is carried over the IP network in such a way that the FC fabric and all FC devices on
the fabric are unaware of the presence of the IP Network.
Figure 1-15 FCIP Actions
FCIP Network Structures
This section describes typical FCIP network structures. In all of these examples, a management station
(not shown) manages the storage routers through an IP network connected to the management interface
and/or HA interface of each storage router.
Figure 1-14 represents a basic, non-redundant structure of an FCIP network configuration. An FC host
or FC device connects to one or more Fibre Channel interfaces of each peer SN 5428-2 Storage Router
deployed for FCIP. Each SN 5428-2 connects to the IP network through one of its Gigabit Ethernet
interfaces. Through the IP network, each FCIP instance accesses its peer, thereby connecting the SANs.
IP
Transporting FC frames
between SAN and an
SN 5428-2 deployed
for FCIP.
Encapsulating FC frames
in IP packets and
transporting IP packets
to peer SN 5428-2.
Transporting FC
frames between
an SN 5428-2
deployed for FCIP
and SAN.
SN 5428-2 SN 5428-2
91008
FC hosts and
storage devices
FC hosts and
storage devices
SAN
SAN