Support Policies for RHEL High Availability clusters - Transport Protocols

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Applicable Environments

  • Red Hat Enterprise Linux (RHEL) 6 or 7 with the High Availability Add-On

Useful References and Guides


This guide lays out Red Hat's policies regarding the communication transport protocols available for usage in RHEL High Availability clusters. Users of RHEL High Availability clusters should adhere to these policies in order to be eligible for support from Red Hat with the appropriate product support subscriptions.


udpu transport: Red Hat's support for this transport protocol is subject to the following conditions:

  • RHEL 7: udpu transport is supported on all package releases
  • RHEL 6 minimum package releases for Red Hat support of udpu: corosync-1.4.1-4.el6, cman-
  • Nodes can not be added to the cluster "on-the-fly" when using this transport. Rather, the cluster must be completely stopped, then started again with an updated configuration containing the new full member list.

udp transport with broadcast messaging: Red Hat's support for broadcast messaging mode within the udp transport is subject to the following conditions:

  • Broadcast may not be used in clusters utilizing an IPv6 network as the interconnect. Either udp with multicast or udpu must be used.