150
Managing a Switch Stack
When the failed master resumes normal operation, it joins the stack as a
member (not a master) if the new stack master has already been elected.
The stack master copies its running configuration to the standby unit
whenever it changes (subject to some restrictions to reduce overhead). This
enables the standby unit to take over the stack operation with minimal
interruption if the stack master becomes unavailable.
Operational state synchronization also occurs:
• when you save the running configuration to the startup configuration on
the stack master.
• when the backup unit changes.
What is Nonstop Forwarding?
Networking devices are often described in terms of three semi-independent
functions called the forwarding plane, the control plane, and the
management plane. The forwarding plane forwards data packets and is
implemented in hardware. The control plane is the set of protocols that
determine how the forwarding plane should forward packets, deciding which
data packets are allowed to be forwarded and where they should go.
Application software on the stack master acts as the control plane. The
management plane is application software running on the stack master that
provides interfaces allowing a network administrator to configure the device.
The Nonstop Forwarding (NSF) feature allows the forwarding plane of stack
units to continue to forward packets while the control and management
planes restart as a result of a power failure, hardware failure, or software fault
on the stack master. This type of operation is called nonstop forwarding.
When the stack master fails, only the switch ASICs on the stack master need
to be restarted.
To prevent adjacent networking devices from rerouting traffic around the
restarting device, the NSF feature uses the following three techniques:
1
A protocol can distribute a part of its control plane to stack units so that
the protocol can give the appearance that it is still functional during the
restart.
2
A protocol may enlist the cooperation of its neighbors through a technique
known as graceful restart.
Содержание PowerConnect 8024
Страница 48: ...48 Contents ...
Страница 52: ...52 Introduction ...
Страница 86: ...86 Switch Features ...
Страница 140: ...140 Setting Basic Network Information ...
Страница 178: ...178 Managing a Switch Stack ...
Страница 204: ...204 Configuring Authentication Authorization and Accounting ...
Страница 272: ...272 Managing General System Settings ...
Страница 308: ...308 Configuring SNMP ...
Страница 336: ...336 Managing Images and Files ...
Страница 354: ...354 Auto Image and Configuration Update ...
Страница 385: ...Monitoring Switch Traffic 385 Figure 16 26 Configure Additional Port Mirroring Settings 9 Click Apply ...
Страница 468: ...468 Configuring Port Characteristics ...
Страница 509: ...Configuring Port and System Security 509 Figure 20 12 Configure Port Security Settings 5 Click Apply ...
Страница 512: ...512 Configuring Port and System Security ...
Страница 550: ...550 Configuring Access Control Lists ...
Страница 571: ...Configuring VLANs 571 Figure 22 6 Add Ports to VLAN 4 Click Apply 5 Verify that the ports have been added to the VLAN ...
Страница 580: ...580 Configuring VLANs Figure 22 17 GVRP Port Parameters Table ...
Страница 586: ...586 Configuring VLANs Figure 22 24 Double VLAN Port Parameter Table ...
Страница 618: ...618 Configuring VLANs ...
Страница 631: ...Configuring the Spanning Tree Protocol 631 Figure 23 5 Spanning Tree Global Settings ...
Страница 637: ...Configuring the Spanning Tree Protocol 637 Figure 23 11 RSTP LAG Settings ...
Страница 685: ...Configuring Port Based Traffic Control 685 Figure 25 3 Storm Control 5 Click Apply ...
Страница 776: ...776 Snooping and Inspecting Traffic Figure 27 17 DAI Interface Configuration Summary ...
Страница 790: ...790 Snooping and Inspecting Traffic ...
Страница 797: ...Configuring Link Aggregation 797 To view or edit settings for multiple LAGs click Show All ...
Страница 894: ...894 Configuring DHCP Server Settings ...
Страница 928: ...928 Configuring L2 and L3 Relay Features Figure 34 3 DHCP Relay Interface Summary ...
Страница 955: ...Configuring OSPF and OSPFv3 955 Figure 35 1 OSPF Configuration ...
Страница 1030: ...1030 Configuring OSPF and OSPFv3 ...
Страница 1068: ...1068 Configuring VRRP ...
Страница 1092: ...1092 Configuring IPv6 Routing ...
Страница 1112: ...1112 Configuring DHCPv6 Server and Relay Settings Relay Interface Number Vl100 Relay Remote ID Option Flags ...
Страница 1119: ...Configuring Differentiated Services 1119 Figure 40 5 DiffServ Class Criteria ...
Страница 1126: ...1126 Configuring Differentiated Services Figure 40 14 DiffServ Service Summary ...
Страница 1142: ...1142 Configuring Differentiated Services ...
Страница 1148: ...1148 Configuring Class of Service Figure 41 1 Mapping Table Configuration CoS 802 1P ...
Страница 1160: ...1160 Configuring Class of Service ...
Страница 1164: ...1164 Configuring Auto VoIP Figure 42 2 Auto VoIP Interface Configuration ...
Страница 1230: ...1230 Managing IPv4 and IPv6 Multicast Figure 43 51 DVMRP Next Hop Summary ...
Страница 1256: ...1256 Managing IPv4 and IPv6 Multicast ...
Страница 1266: ...1266 Feature Limitations and Platform Constants ...
Страница 1274: ...1274 System Process Definitions ...
Страница 1294: ...Index 1294 ...