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Hello all, my first post...so be gentle 😆
I have a 3120 with two different internet connections, both ethernet based.
The first plugs into the eth 0/1 interface and has several static IP addresses assigned
The second plugs into interface switchport 0/1 and is now connected to a bridemode DSL modem
So now that I no longer have a private IP address for the switchport, what config change is required to allow internet traffic to flow out that port?
I attempted to change it to unnumbered - but it's not working.
Ideas?
Thanks in advance
Mark
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It appears you already have the primary Internet connection setup with a network monitor ping probe to monitor the status of the link, and if the probe fails the default route is to be removed causing the Internet connection to failover. Therefore, there are only a few pieces of configuration that need to be done in order to have the new connection take over when the primary fails.
Also, I recommend you remove the administrative distance on the current default route. In the current configuration you have an administrative distance of "2" configured on the primary default route. This should be removed.
- Configure an IP address for the new backup Internet connection (VLAN 2)
- Configure a new default route for the backup Internet connection
- Create a new policy-class for the backup Internet connection and assign it to the new Internet connection interface (VLAN 2)
- Create a new source NAT statement for the backup Internet connection
1. To configure the new IP address for VLAN 2 do the following:
# configure terminal
(config)# interface vlan 2
(config-intf-vlan 2)# ip address <ip address> <subnet mask>
(config-intf-vlan 2)# no shutdown
(config-intf-vlan 2)# end
2. To configure a default route out the new Internet connection do the following:
# configure terminal
(config)# ip route 0.0.0.0 0.0.0.0 <ip address of ISP's default-gateway> <administrative distance value (i.e. 2)>
3. To create a new policy-class and assign it to the new Internet interface do the following:
# configure terminal
(config)# ip policy-class Public2
(config-policy-class)# exit
(config)# interface vlan 2
(config-intf-vlan 2)# ip access-policy Public2
(config-intf-vlan 2)# end
4. To create a new source NAT statement on the Private policy-class do the following:
# configure terminal
(config)# ip policy-class Private
(config-policy-class)# nat source list wizard-ics interface vlan 2 overload policy Public2
Finally, save the configuration.
For additional information and future reference this information is covered in the Configuring Network Monitor in AOS document.
Please, let me know if you have any questions or additional information.
Levi

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Re: Backup DSL changing to bridged mode
Thank you for asking this question in the support community and for providing the configuration. We will need some additional information about the network to assist you further. When you get a chance, will you reply with the following information:
- Is the ISP assigning you a static public IP address to be used on the DSL modem connection, or are they giving you an address via DHCP?
- How will you be using the DSL modem connection? Will it be for Internet failover/backup or Internet load-sharing?
Please, reply to this post with any additional questions and information. I will be happy to help in any way I can.
Levi

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Re: Backup DSL changing to bridged mode
The Frontier DSL has a single static IP address, and the backup connection is used for failover only.
Thanks

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It appears you already have the primary Internet connection setup with a network monitor ping probe to monitor the status of the link, and if the probe fails the default route is to be removed causing the Internet connection to failover. Therefore, there are only a few pieces of configuration that need to be done in order to have the new connection take over when the primary fails.
Also, I recommend you remove the administrative distance on the current default route. In the current configuration you have an administrative distance of "2" configured on the primary default route. This should be removed.
- Configure an IP address for the new backup Internet connection (VLAN 2)
- Configure a new default route for the backup Internet connection
- Create a new policy-class for the backup Internet connection and assign it to the new Internet connection interface (VLAN 2)
- Create a new source NAT statement for the backup Internet connection
1. To configure the new IP address for VLAN 2 do the following:
# configure terminal
(config)# interface vlan 2
(config-intf-vlan 2)# ip address <ip address> <subnet mask>
(config-intf-vlan 2)# no shutdown
(config-intf-vlan 2)# end
2. To configure a default route out the new Internet connection do the following:
# configure terminal
(config)# ip route 0.0.0.0 0.0.0.0 <ip address of ISP's default-gateway> <administrative distance value (i.e. 2)>
3. To create a new policy-class and assign it to the new Internet interface do the following:
# configure terminal
(config)# ip policy-class Public2
(config-policy-class)# exit
(config)# interface vlan 2
(config-intf-vlan 2)# ip access-policy Public2
(config-intf-vlan 2)# end
4. To create a new source NAT statement on the Private policy-class do the following:
# configure terminal
(config)# ip policy-class Private
(config-policy-class)# nat source list wizard-ics interface vlan 2 overload policy Public2
Finally, save the configuration.
For additional information and future reference this information is covered in the Configuring Network Monitor in AOS document.
Please, let me know if you have any questions or additional information.
Levi

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Re: Backup DSL changing to bridged mode
I went ahead and flagged this post as “Assumed Answered.” If any of the responses on this thread assisted you, please mark them as either Correct or Helpful answers with the applicable buttons. This will make them visible and help other members of the community find solutions more easily. If you still need assistance, I would be more than happy to continue working with you on this - just let me know in a reply.
Levi

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Re: Backup DSL changing to bridged mode
I went ahead and flagged the "Correct Answer" on this post to make it more visible and help other members of the community find solutions more easily. If you don't feel like the answer I marked was correct, feel free to come back to this post and unmark it and select another in its place with the applicable buttons. If you still need assistance, we would be more than happy to continue working with you on this - just let us know in a reply.
Thanks,
Noor