A cluster is a group of servers with virtual machines running on them. Cluster nodes are physical servers. Before adding a cluster node, please make sure that the server is ready to operate as a cluster node in accordance with the article Cluster node configuration.

This article describes how to add a new cluster node.

Navigate to Cluster settings → Cluster nodes→ Add.

  • Has root password — select this check box to allow authentication with the root password; 
  • Password — enter the root password;
  • — enter the SSH-key to connect to the server;
  • IP address — server IP address;
  • Name — enter a name for the cluster node;
  • Maximum number of  containers  — enter the maximum number of containers that can run on the cluster node; 
  • Notes — additional information that will be displayed in the Status column in the list of cluster nodes.

We recommend that you update QEMU and libvirt right after you have added the cluster node:

yum install centos-release-qemu-ev yum update
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When adding a new server into the cluster, VMmanager and virtualization packages are installed.

sysctl.conf configuration:

  1. The system enables forwarding of packages:

    net.ipv4.ip_forward = 1
net.ipv4.conf.default.forwarding = 1
net.ipv6.conf.default.forwarding = 1
net.ipv6.conf.all.forwarding = 1
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  2. Disables Proxy ARP:

    net.ipv4.conf.default.proxy_arp = 0
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  3. Enables check of routing from the source: 

    net.ipv4.conf.all.rp_filter = 1
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  4. Enables "magic-sysrq key":

    kernel.sysrq = 1
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  5. Sets up package redirects:

    net.ipv4.conf.default.send_redirects = 1
net.ipv4.conf.all.send_redirects = 0
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  6. Enables  Neighbour Discovery Protocol (NDP) for IPv6:

    net.ipv6.conf.default.proxy_ndp = 1
net.ipv6.conf.all.proxy_ndp = 1
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