Storage Area Networks

1
Storage Area Networks
2
Whats SANs
3
SAN Solutions

• Server consolidation
• Storage consolidation
• Port consolidation
• Tape consolidation
• Distance

4
SAN Hardware
5
Switches and Hubs
FC-AL and Switching Fabric (non-blocking)
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FibreChannel

• How SCSI Limitations are Addressed
• Speed
• Distance
• Device Count
• Access

7
FibreChannel Speed

• 266 Mbps ten years ago
• 1063 Mbps common in 1998
• 2125 Mbps available today
• 4 Gbps near future products
• Backward compatible to 1 2 Gbps
• 10 Gbps 2005?

8
I/O Protocols over IP

• IP Networking is ubiquitous
• Gigabit ethernet is here
• 10Gbps ethernet is just becoming available
• Dont have to invest in a second network
• Just upgrade the one you have ?
• IP Ethernet software is well understood
• Existing talent pool for vendors to leverage
• Developers, not end-user Network Engineers

9
FibreChannel Distance

• 1063 Mbps
• 175m (62.5 um multi-mode)
• 500m (50.0 um multi-mode)
• 10 km (9 um single-mode)
• 2125 Mbps
• 500m (50.0 um multi-mode)
• 2 km (9 um single-mode)

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FibreChannel - Topology

• Point-to-Point
• Direct Connection of Server and Storage Node
• Arbitrated Loop
• Up to 126 Devices in a Loop via NL_Ports
• Token-access, Polled Environment (like FDDI)
• Fabric
• Arbitrary Topology
• Requires At Least One Switch
• Up to 15 million ports can be concurrently logged
  in with the 24-bit address ID.
• Dedicated Circuits between Servers Storage
• via Switches

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Other Features/Issues

• Backup
• LAN-free, server-less
• Replication
• Synchronous/Asynchronous
• Server Clustering
• Volume and File Management