HP StorageWorks 4000/6000/8000 - Enterprise Virtual Arrays, Справочное руководство

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Table 175 lists the network requirements for long-distance IP gateways that are supported with XP
Continuous Access.
Table 175 Network requirements for long-distance IP gateways with XP Continuous Access
Requirement Specification
• Must be dedicated to the XP Continuous Access storage replication
function.
• The minimum IP bandwidth required for XP Continuous Access is 16
Mb/s per path.
• When configuring multiple long-distance links, ensure all links provide
equal bandwidth and latency for maximum sustained aggregate
nl
performance. If any single link has reduced performance or increased
latency, all links will be reduced to the lowest performing link, signi-
ficantly lowering the aggregate performance.
• There is no support for dynamic pacing of the gateway.
Bandwidth
1
1,500 bytes: HP StorageWorks IP Distance Gateway (mpx100)
2,348 bytes: B-series 400 MP Router, MP Router Blade
3,000 bytes: C-series MDS 9222i, 9216i, IPS-8, IPS-4, 14/2
Note: These MTU settings are the recommended maximum values when
using the respective FCIP products. You must ensure that the connected
network components support the same values for end-to-end connectivity
at the stated rates.
MTU of the IP network
See Table 167 , Table 168 , and Table 169 .
Maximum latency
1
Low-loss network: 0.0012% average over 24 hours
High-loss network: 0.2% average over 24 hours; must not exceed 0.5%
for more than 5 minutes in a two-hour window
Average packet-loss ratio
2
Must not exceed 10 ms over 24 hours
Latency jitter
3
1
Pre-existing restriction
2
A high packet-loss ratio indicates the need to retransmit data across the ISL. Each retransmission delays transmissions queued
behind the current packet, thus increasing the time to complete pending transactions. Unless noted otherwise, gateways listed
in
Table 176 are supported in both low-loss and high-loss networks.
3
Latency jitter is the difference between the minimum and maximum values, and indicates how stable or predictable the network
delay is. The greater the jitter, the greater the variance in the delay, which lowers the performance predictability.
NOTE:
Applications typically require more than the minimum bandwidth to meet throughput requirements.
See the
HP StorageWorks XP Continuous Access user guide for details on link sizing.
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