1. Cisco Storage Networking iSCSI
James Long
Storage Networking Systems Engineer

2. Why use iSCSI?
Performance/cost benefits provided by competition in Internet marketplace
Economies of scale from installing and operating a single type of network
Lower TCO via unified management architecture
Plethora of IP management, security, troubleshooting and QoS solutions
Extended distance
Connectivity to carrier-class services
Ubiquitous supply of skilled personnel

3. What does iSCSI do for me?
iSCSI Enabled Servers
Provides storage accessibility from many server operating systems across the IP network.
Provides an alternative to Fibre Channel island problem.
Utilizes existing IP network security, quality of service, and prioritization features.
Allows usage of existing management infrastructure.
“IP/SAN boot”
NT 4.0
Win2K
Linux
Solaris
(G:)
(F:)
(K:)
(L:)
Gigabit Ethernet
iSCSI
Fibre Channel
(G:)
(F:)
(K:)
(L:)
Catalyst Switch IP

4. iSCSI Adds Connectivity Options for Mid-Range Servers
iSCSI hosts are discovered, displayed and configured through Fabric Manager
iSCSI hosts are bound to virtual WWNs creating a static relationship enabling:
Zoning of iSCSI initiators
Accounting against iSCSI initiators
Topology mapping of iSCSI initiators
iSCSI offers HA features such as GEC, VRRP and FC port trespass
iSCSI connectivity is ‘fanned-out’ using Ethernet switches
Ratio is determined by application I/O requirements
CHAP-based authentication
iSCSI driver is loaded onto hosts
No additional cost for host adapter
OS native iSCSI drivers available today from every major OS vendor
Cisco also provides free iSCSI drivers
Cisco IP Storage Switching Module
IP-VRRP support for redundant IP gateway services
iSCSI
iSCSI-enabled hosts
iSCSI Login registering iQN
iSCSI qualified names are defined within iSCSI client
iQN1
iQN2
Cisco Catalyst 6500 Multilayer LAN Switches
iQN2 is mapped to an allocated pWWN and registered in the fabric
iQN2 = pWWN2

5. Integrated iSCSI Benefits
Bolt-on
Built-in
Complex HA or none
Interop issues
Finger pointing
Convoluted management
Separate roadmaps
Inherent HA
No interop concerns
No finger pointing
Simplified management
Synchronized roadmaps

6. Internet Storage Name Server (iSNS)
iSNS Server
Automates iSCSI device discovery, configuration and management
Directory-based protocol for management of IPS devices
Device registration
Device discovery
Zoning via Discovery Domains
State Change Notification (SCN)
iSNS client in MDS registers FC information with external iSNS servers
FC Devices
Zoning membership
SCN relay
iSNS server in MDS imports FC information from FC Name Server (FCNS)
iSCSI Servers
iSCSI Servers
IP Network
iSNS Client
MDS + IPS8
FC Fabric
FC Storage
FC Storage
FC Servers

7. iSCSI secured with IPsec
IPSec for iSCSI
iSCSI secured with IPsec
iSCSI Server
LAN
MDS w/ MPS-14/2
Standards-based IPsec protocol suite for comprehensive security of iSCSI traffic
End-to-end authentication, data integrity and confidentiality
Hardware based, high performance solution
MDS 9216i and MPS-14/2 module

8. iSCSI Network Boot Protocol (iNBP)
Fibre Channel
Master host IP
Network FC
Host 1 image
iSCSI
Ethernet
Host 1
MDS 9000
w/ IPS Module
Cisco iSCSI Drivers
Install Windows 2000 on master host C: drive
Install Cisco iSCSI driver on master host
Configure & mount iSCSI target
Run Cisco copy utility which does the following:
Copies boot image from Master host to iSCSI target
Configures Windows for the new host
Set PXE boot option in host 1
Repeat for additional hosts

9. Additional iSCSI Features
Proxy-iSCSI Initiator Mode
Presents all iSCSI Initiators to storage subsystem as a single initiator
Minimizes the configuration tasks required to enable large scale iSCSI deployment:
Storage device configuration
Zoning
Auto-trespass command can be issued when IPS module detects failures on active path
iSCSI topology mapping via Fabric Manager
LUN re-mapping

10. iSCSI Software Drivers
Qual Status
IBM
Windows (MSFT & CSCO)
Solaris 8, 9 (CSCO)
AIX 5.2 and 5.3 (IBM)
HDS
Linux HP
HP-UX (HPQ)
EMC
Windows (MSFT)
Linux (TBD)
Cisco iSCSI software drivers
Microsoft: Win2000 and Win2003
HP: HPUX 10.2 and 11.0
IBM: AIX 4.3.3, 5.1, and 5.2
SUN: Solaris 2.6, 2.7, 2.8, 2.9
Linux: Kernel or higher and 2.6.1
Native iSCSI software drivers
Microsoft: Windows 2000/Server 2003
HP: HPUX 11.23
IBM: AIX 5.2 and 5.3

11. iSCSI Impact on CPU
Microsoft Exchange is representative of messaging/collaboration applications
Requires large volume of storage, but relatively little throughput
Minimal CPU utilization for iSCSI software driver vs. FC HBA
Use iSCSI TOE for high throughput applications - current vendors include Adaptec, Alacritech, Emulex, Qlogic, et alia
Storage Network Throughput
Server CPU Utilization
MB/s
Theoretical Maximum Throughput
of 100Mbps Ethernet
% CPU Utilization
# of Users
# of Users

12. iSCSI Design Option 1: Shared Ethernet, Shared NIC
Pros:
Inexpensive
Easy to implement
Fast deployment time
Cons:
Could overload ISL bandwidth
Could impact other apps
Jumbo frames
QoS policy changes
Support becomes entangled
Switch/router patches
Scheduled downtime
Weak security
Troubleshooting is complex
Low host performance
Poor host monitoring/trending
iSCSI Servers
Existing IP Network
MDS IPS-8
FC Fabric
FC Storage
FC Servers

13. iSCSI Design Option 2: Dedicated VLAN, Shared NIC
Pros:
Potentially inexpensive
Somewhat easy to implement
Fast deployment time
Troubleshooting is somewhat simplified
Cons:
Could overload ISL bandwidth
Could impact other apps
Jumbo frames
QoS policy changes
Support becomes entangled
Switch/router patches
Scheduled downtime
Medium security
Troubleshooting is still complex
Low host performance
Poor host monitoring/trending
Could require host upgrades
iSCSI Servers
VLAN Enabled Existing IP Network
MDS IPS-8
FC Fabric
FC Storage
FC Servers

14. iSCSI Design Option 3: Dedicated VLAN, Dedicated NIC
Pros:
Potentially inexpensive
Somewhat easy to implement
Potentially fast deployment time
Troubleshooting is somewhat simplified
Medium host performance
Good host monitoring/trending
Cons:
Could overload ISL bandwidth
Could impact other apps
Jumbo frames
QoS policy changes
Support becomes entangled
Switch/router patches
Scheduled downtime
Medium security
Troubleshooting is still complex
Could require host upgrades
iSCSI Servers
VLAN Enabled Existing IP Network
MDS IPS-8
FC Fabric
FC Storage
FC Servers

15. iSCSI Design Option 4: Dedicated LAN
Pros:
Troubleshooting is simplest
Best host performance
Good host monitoring/trending
No additional load on existing ISLs
No impact to other Apps
Jumbo frame capable
No QoS policy changes
Separate support model
Strong security
Cons:
Most expensive
Laborious to implement
Slow deployment time
Could require host upgrades
iSCSI Servers
New Ethernet LAN
Existing IP Network
MDS IPS-8
FC Fabric
FC Storage
FC Servers

16. Best Current Practice for iSCSI Redundancy