HP Mellanox SX1018 Mellanox MLNX-OS User Manual for SX1018HP Ethernet Managed - Page 66

Spanning Tree

Get HP Mellanox SX1018 PDF manuals and user guides View all HP Mellanox SX1018 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 66 highlights

5.5 Spanning Tree Rev 1.6.2 5.5.1 Rapid Spanning Tree Protocol The operation of Rapid Spanning Tree Protocol (RSTP) provides for rapid recovery of connectivity following the failure of a bridge/bridge port or a LAN. The RSTP component avoids this delay by calculating an alternate root port, and immediately switching over to the alternate port if the root port becomes unavailable. Thus, using RSTP, the switch immediately brings the alternate port to forwarding state, without the delays caused by the listening and learning states. The RSTP component conforms to IEEE standard 802.1D 2004. 5.5.2 RSTP Enhancements RSTP enhancement is a set of functions added to increase the volume of RSTP in Mellanox switches. It adds a set of capabilities related to the behavior of ports in different segments of the network. For example: the required behavior of a port connected to a non-switch entity, such as host, is to converge quickly, while the required behavior of a port connected to a switch entity is to converge based on the RSTP parameters. Additionally, it adds security issues on a port and switch basis, allowing the operator to determine the state and role of a port or the entire switch should an abnormal event occur. For example: If a port is configured to be root-guard, the operator will not allow it to become a root-port under any circumstances, regardless of any BPDU that will have been received on the port. The following are the RSTP enhancement set of functions: • Port type • Can be configured on the switch level. It is applied to each interface if the interface was not specifically configured with this property. spanning-tree port type {edge , normal , network} default • Can be configured on the interface level spanning-tree port type {edge , normal, network} • The edge port is not assumed to be converged by the RSTP learning/forwarding mechanism. It converges to forwarding quickly. • The normal port is assumed to be connected to a switch, thus it tries to be converged by the RSTP learning/forwarding. However, if it does not receive any BPDU[s], it is operationally moved to be edge. • The network port is assumed to be connected to a switch. If it does not receive any BPDU[s], it is moved to discarding state. • Per interface BPDU-filter: Decides on whether or not to receive/transmit BPDU[s] spanning-tree bpdufilter {enable , disable} • Per interface guard spanning-tree guard {loop , root} • Setting the interface guard to guard root on a port assures the port is not a root-port • Setting the interface to guard loop on a port assures the port is not forwarded if it seizes from the receiving BPDU[s] • Per interface priority: Applies priority to a port to make the port move to Root-Port or Alternate-Discarding. spanning-tree port-priority [0 -240] Mellanox Technologies 66

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
Rev 1.6.2
Mellanox Technologies
66
5.5
Spanning Tree
5.5.1
Rapid Spanning Tree Protocol
The operation of Rapid Spanning Tree Protocol (RSTP) provides for rapid recovery of connectiv-
ity following the failure of a bridge/bridge port or a LAN. The RSTP component avoids this
delay by calculating an alternate root port, and immediately switching over to the alternate port if
the root port becomes unavailable. Thus, using RSTP, the switch immediately brings the alternate
port to forwarding state, without the delays caused by the listening and learning states. The RSTP
component conforms to IEEE standard 802.1D 2004.
5.5.2
RSTP Enhancements
RSTP enhancement is a set of functions added to increase the volume of RSTP in Mellanox
switches. It adds a set of capabilities related to the behavior of ports in different segments of the
network. For example: the required behavior of a port connected to a non-switch entity, such as
host, is to converge quickly, while the required behavior of a port connected to a switch entity is
to converge based on the RSTP parameters.
Additionally, it adds security issues on a port and switch basis, allowing the operator to deter-
mine the state and role of a port or the entire switch should an abnormal event occur. For exam-
ple: If a port is configured to be root-guard, the operator will not allow it to become a root-port
under any circumstances, regardless of any BPDU that will have been received on the port.
The following are the RSTP enhancement set of functions:
•
Port type
•
Can be configured on the switch level. It is applied to each interface if the interface was not specif-
ically configured with this property.
spanning-tree port type {edge , normal , network} default
•
Can be configured on the interface level
spanning-tree port type {edge , normal, network}
•
The
edge port
is not assumed to be converged by the RSTP learning/forwarding mechanism. It con-
verges to forwarding quickly.
•
The
normal port
is assumed to be connected to a switch, thus it tries to be converged by the RSTP learn-
ing/forwarding. However, if it does not receive any BPDU[s], it is operationally moved to be edge.
•
The
network port
is assumed to be connected to a switch. If it does not receive any BPDU[s], it is
moved to discarding state.
•
Per interface BPDU-filter: Decides on whether or not to receive/transmit BPDU[s]
spanning-tree bpdufilter {enable , disable}
•
Per interface guard
spanning-tree guard {loop , root}
•
Setting the interface guard to
guard root
on a port assures the port is not a root-port
•
Setting the interface to
guard loop
on a port assures the port is not forwarded if it seizes from the
receiving BPDU[s]
•
Per interface priority: Applies priority to a port to make the port move to Root-Port or
Alternate-Discarding.
spanning-tree port-priority [0 -240]