Chapter 13
| Basic Administration Protocols
Ethernet Ring Protection Switching
– 471 –
command. As such, two or more forced switches are allowed in the
ring, which may inadvertently cause the segmentation of an ring. It
is the responsibility of the operator to prevent this effect if it is
undesirable.
Ring protection requests, commands and R-APS signals have the
priorities as specified in the following table.
■
Recovery for forced switching under revertive and non-revertive
mode is described under the Revertive parameter.
■
When a ring is under an FS condition, and the node at which an FS
command was issued is removed or fails, the ring remains in FS
state because the FS command can only be cleared at node where
the FS command was issued. This results in an unrecoverable FS
condition.
When performing a maintenance procedure (e.g., replacing,
upgrading) on a ring node (or a ring link), it is recommended that FS
commands be issued at the two adjacent ring nodes instead of directly
issuing a FS command at the ring node under maintenance in order to
avoid falling into the above mentioned unrecoverable situation.
Table 31: ERPS Request/State Priority
Request / State and Status
Type
Priority
Clear
local
highest
FS
local
|
R-APS (FS)
remote
|
local SF
*
*
If an Ethernet Ring Node is in the Forced Switch state, local SF is ignored.
local
|
local clear SF
local
|
R-APS (SF)
remote
|
R-APS (MS)
remote
|
MS
local
|
WTR Expires
local
|
WTR Running
local
|
WTB Expires
local
|
WTB Running
local
|
R-APS (NR, RB)
remote
|
R-APS (NR)
remote
lowest
Содержание GTL-2881
Страница 30: ...Figures 30 Figure 450 Showing RIP Peer Information 669 Figure 451 Resetting RIP Statistics 670 ...
Страница 34: ...Section I Getting Started 34 ...
Страница 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Страница 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Страница 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Страница 229: ...Chapter 8 Congestion Control Automatic Traffic Control 229 Figure 135 Configuring ATC Interface Attributes ...
Страница 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Страница 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Страница 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Страница 670: ...Chapter 18 Unicast Routing Configuring the Routing Information Protocol 670 Figure 451 Resetting RIP Statistics ...
Страница 672: ...Section III Appendices 672 ...
Страница 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Страница 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Страница 696: ...Glossary 696 ...
Страница 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...