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DLSw Ethernet Redundancy - Issue !?

Dear All Expert,

Good day.

Currently, i have a issue of the DLsw ER+ and i hope that DLSw+ Netpro Experts can highlight/advice my problem.

Problem Description:

Please refer the diagram - dlsw+.jpg first.

Early, my network did configure the #bridge-group 1 in both Fast-Ethernet of Router A and B, but it suffer the common dlsw issue

•Unreliable Local Reachability Information

•Circuit Contention

•Undetected Looping Explorers

After removing one #bridge-group 1 from Router B Fast-Ethernet, the network become stable already.

Now i still look for the DLsw Ethernet redundancy solution (Purpose = Router A as primary and Router B will take over role A

in case Router A down), and do some research.


URL 1 -

URL 2 -

URL 3 -


But, it look like my problem more suitable to use cisco solution << URL 2 - Figure 6 DLSw+ with Ethernet Redundancy Enabled >>

Example from URL 2:


Router B

dlsw local-peer peer id

dlsw remote-peer 0 tcp

int e1

ip address

dlsw transparent redundancy-enable 9999.9999.9999

Router A

dlsw local-peer peer-id

dlsw remote-peer 0 tcp

int e1

ip address

dlsw transparent redundancy-enable 9999.9999.9999 master priority 1

dlsw transparent timers sna 1500


Now my concerns are

1. It is really suitable to use the URL2 solution ? or Dlsw passive and backup-peer are better ?

2. If using URL2 solution, is it following the multicast MAC-address 9999.9999.9999 ? How to choose the MAC address ?

3. Should i still put the #bridge-group 1 command into both Fast-Ethernet of Router A and B ? If still working without the #bridge-group 1 command ?

4. Just review the URL3, and it is more complicated. Because it has to configure each MAC-address in the Fast-Ethernet and #dlsw transparent Map. Is it neccessary to use #dlsw transparent map or the URL2 will do it as well.

FYI - the current dlsw config of router A and B


dlsw local-peer peer-id

dlsw timer explorer-wait-time 3

dlsw timer explorer-delay-time 1

dlsw timer connect-timeout 600

dlsw timer local-connect-timeout 15

dlsw rsvp default

dlsw remote-peer 0 tcp host-netbios-out XXX

dlsw remote-peer 0 tcp

dlsw remote-peer 0 tcp

dlsw bridge-group 1

dlsw circuit-keepalives

int fa0/0

bridge-group 1 (only in router A now)


Please kindly help it.




Re: DLSw Ethernet Redundancy - Issue !?

DLSw+ local switching is not supported between two Ethernet redundancy interfaces, or between an Ethernet redundancy interface and any other LAN-type media (Token Ring, ISL, LANE, or FDDI).

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