lb useful link

https://zhuanlan.zhihu.com/p/210624543

https://techdocs.akamai.com/cloud-computing/docs/configuring-ip-failover-over-bgp-using-frr-advanced

https://docs.tigera.io/calico/latest/getting-started/bare-metal/about

https://www.reddit.com/r/networking/comments/ba7nbl/bgp_for_vip_advertisement_load_balancer/

https://blog.csdn.net/u014443578/article/details/136902252

https://github.com/uber/kraken

https://github.blog/engineering/introducing-glb/