Nodes' System Parameters

Check Items

Check whether the system parameters on your node meet the expectation.

Solution

• Scenario 1: If the MTU value of the bond0 network on your BMS node is not the default value 1500, this check item will fail.

  Non-default parameter settings may lead to service packet loss. Change them back to the default values. Take the following steps:

  1. Disable bond0.

     sudo ip link set dev bond0 down

     

     Disabling bond0 will interrupt services. Exercise caution when performing this operation.

  2. Change the MTU value to 1500.

     sudo ip link set dev bond0 mtu 1500

  3. Restart bond0.

     sudo ip link set dev bond0 up

  4. Verify the modification result. (Ensure that the MTU has been updated.)

     ip link show dev bond0 | grep mtu

     If the command output is mtu 1500, the setting has been modified.

• Scenario 2: When upgrading a cluster to v1.29 or later, kube-proxy manages the nf_conntrack_max kernel parameter. If the current nf_conntrack_max value exceeds the conntrack-min configured for kube-proxy, this check fails.
  You are advised to use kube-proxy's conntrack-min startup parameter to ensure that nf_conntrack_max is not reduced below its current value after the upgrade.

  1. Check the current nf_conntrack_max value.

     cat /proc/sys/net/netfilter/nf_conntrack_max

  2. Modify kube-proxy's conntrack-min through node pool configuration. Set it to the value of the nf_conntrack_max kernel parameter on the current node (the value obtained in the previous step).