1. Problem Description Related Pods 1 2 3 4 5 6 kubectl -n istio-system get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES istiod-647c7c9d95-7n7n6 1/1 Running 0 77m 10.244.173.51 docs-ai-a800-4 <none> <none> istiod-647c7c9d95-k6l88 1/1 Running 0 30m 10.244.210.160 ai-a40-2 <none> <none> istiod-647c7c9d95-pj82r 1/1 Running 0 51m 10.

1. Symptoms Pod information can be viewed 1 2 3 4 kubectl -n my-testns get pod my-testpod NAME READY STATUS RESTARTS AGE my-testpod 1/1 Running 0 2d13h Pod logs cannot be viewed 1 2 3 kubectl -n my-testns logs my-testpod -f Error from server (NotFound): the server could not find the requested resource ( pods/log my-testpod) On the host where the Pod runs, the container logs can be viewed with docker logs.

1. Testing the Full Bandwidth Start the iperf3 server on the target host 1 2 3 4 5 iperf3 -s ----------------------------------------------------------- Server listening on 5201 ----------------------------------------------------------- Test from the client host 1 iperf3 -c x.x.x.x -p 5201 -t 10 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Connecting to host x.

1. Subnet Management by kube-controller-manager kube-controller-manager has many controllers; the one related to Pod IP is NodeIpamController. The NodeIpamController mainly manages the podcidr of nodes: when a new node joins the cluster, it allocates a subnet to that node; when a node is deleted, it reclaims the subnet. The subnets

1. Business Background Once an enterprise reaches a certain scale, relying entirely on public cloud infrastructure makes IT costs very high. The cost of purchasing physical machines can be amortized over the next 3 to 5 years, and afterwards the machines are not scrapped; instead they continue to serve beyond their planned lifespan.