BFD MAD ports should be excluded from shutdown?

[Tomas_Kaminskas]

I am a bit confused. Actually there is a configuration example showing more than 2 devices connected in a ring topology with full mesh BFD MAD connections:

http://www.h3c.com.hk/Technical_Support___Documents/Technical_Documents/Switches/H3C_S5800_Series_Switches/Configuration/Typical_Configuration_Example/H3C_S5820X[S5800]_Configuration_Examples-6W100/#_Ref270520212

[parnassus]

I must to admit that BFD MAD requirements and restrictions seem to vary reading documentation (e.g. HPE FlexNetwork 10500 Switch Series versus HPE FlexNetwork 5510 HI Switch Series).

For the HPE FlexNetwork 5510 HI Switch Series, in contrast to what is reported for the bigger HPE FlexNetwork 10500 Switch Series in its IRF Configuration Guide, there is not a clear statement about the Intermediate Device requirement when IRF members are more than two (exactly as it happens reading the H3C documentation reported above which doesn't report that requirement).

See this:

taken from the MAD Mechanisms paragraph of the IRF Configuration Guide for the HPE FlexNetwork 5510 HI Switch Series.

When using the common Ethernet ports...notice the statement: "Each member device has a BFD MAD link to an intermediate device, or all member devices have a BFD MAD link to each other." which admits a Mesh configuration ("all to each other") if the Intermediate Device is not available...at least as I understand it.

Last minute edit:

Among BFD MAD Disadvantages are reported:

• If no intermediate device is used, any two IRF members must have a BFD MAD link to each other.
• If an intermediate device is used, every IRF member must have a BFD MAD link to the intermediate device.

So it seems that the magic of two IRF members' threshold associated with the presence/absence of an Intermediate Device is there.

[Mike_ES]

Hi,

I think for MAD types we should concern what H3C site presenting (reference screen-shoot attached), but:

1. If you have daisy chain topology (min. 3 IRF nodes) , you cannot use LACP MAD without intermediate switch.

2. Also you cannot use BFD MAD with daisy chain , because not having full mesh (BFD sessions between IRF nodes).

So, for 3 IRF nodes you can use LACP MAD with intermediate switch OR you can setup/change to IRF ring topology and having BFD MAD possible.

Michal

[Tomas_Kaminskas]

My setup is IRF ring topology and I cannot understand why one bfd link is UP and another one is DOWN:

[IRF]dis bfd session
Total Session Num: 2 Up Session Num: 1 Init Mode: Active

IPv4 Session Working Under Ctrl Mode:

LD/RD SourceAddr DestAddr State Holdtime Interface
97/97 192.168.2.1 192.168.2.2 Up 1384ms Vlan3
98/0 192.168.2.1 192.168.2.3 Down / Vlan3