I am not checking my emails until Nov 14th, 2025. Thanks, Samaneh On Nov 6, 2025, at 12:07 PM, Marco Moock via NANOG <nanog@lists.nanog.org> wrote: On 06.11.2025 07:18 Vasilenko Eduard wrote: The first time I configured Cisco 2500 with ISP redundancy in 1998. It worked fine: If the link to the primary ISP was down, the office (50 employees company) still have connectivity through the other link. And yes, the office network was not flat - it had many subnets. In case of failure all the connections fail and need to be restablished. That is not something I call redundancy. If you host services inside such a network, both IP addresses must be present in the DNS and that means clients can use any and take some time until they notice the failing connection. An established connection will break this way too. Redundancy is different and means your network is connected by 2 ISP - independent of their address ranges. _______________________________________________ NANOG mailing list https://urldefense.com/v3/__https://lists.nanog.org/archives/list/nanog@list... [lists[.]nanog[.]org]