The underlay CNI solution can meet the needs of low-latency applications, some traditional host applications transporting to the cloud, and storage components requiring independent network to transmit datas.
Currently, there are not many options in the open source community. CNI projects such as macvlan SRIOV ipvlan miss functions like IPAM, clusterip communication. Projects like multus can insert multiple network interface to pod, problems such as routing tuning and IP allocation among multiple network interfaces cannot be solved. There is no IPAM projects in the community to support complicated requirements of underlay IPAM, such as IP dual-stack support, fixed IP for application, IP recycling, IP conflicts, etc..
Spiderpool give IPAM solution, and could integrate macvlan, SRIOV, ipvlan, multus to solve above-mentioned pain points and well integrate various infrastructure resources. It results to a new Underlay network solution.