Db2 cluster services port usage information

Db2 cluster services includes technology from IBM® Tivoli® System Automation for Multiplatforms (Tivoli SA MP) software, IBM Reliable Scalable Clustering Technology (RSCT) software, and IBM Storage Scale software.

For Db2 pureScale® Feature, these IBM Storage Scale and RSCT ports must be kept open:
Table 1. IBM Storage Scale port usage
Service name Port number Protocols
mmfsd (mmfsd64) 11912 TCP/IP
mmsdrserv 11912 TCP/IP
Note:
  1. For more information look for "IBM Storage Scale port usage" in the IBM documentation. A link to IBM Storage Scale version 4.2 is provided for reference. Ensure to use the version of the page corresponding to the running version of the software for the most applicable instructions.
  2. This port number can be customized. The default value is shown.

In addition to the Storage Scale daemon (mmfsd), some IBM Storage Scale commands also require TCP/IP ports to be available during execution. By default, random ports are chosen for these executions. If firewall is set up on each host or in the network, these randomly chosen ports are likely to be blocked, leading to failure of the commands. To work around this, Storage Scale provides a way to specify a range of ports for command execution: mmchconfig tscCmdPortRange=LowNumber-HighNumber

Table 2. Table 2: Pacemaker, Corosync and QDevice port usage
Service name Port number Protocols
Corosync 5404-5412 UDP
Corosync / QNetd 5403 TCP
Pacemaker remote 3121 TCP
pcsd 2224 TCP
Note:

For most HA systems, only the Corosync and QNetd ports are required. Pacemaker remote is not used in current Db2 HA with Pacemaker deployments. pcsd is a Red Hat utility that can interact with the Pacemaker configuration. It is not part of the supported set of tools for Db2 with Pacemaker.

On Red Hat Enterprise Linux, using the firewall-cmd tool, all required Pacemaker / Corosync and QNetd ports can be opened by adding the high-availability service to the firewall rule set.

# Corosync communication
firewall-cmd --permanent --add-service=high-availability
firewall-cmd --reload

For SuSE Enterprise Linux or for Red Hat servers where only a subset of ports are needed, these are the firewall-cmd commands required. The following commands show the port numbers and associated services.

firewall-cmd --permanent --add-port=2224/tcp  # pcsd
firewall-cmd --permanent --add-port=3121/tcp  # pacemaker remote
firewall-cmd --permanent --add-port=5403/tcp  # corosync qnetd
firewall-cmd --permanent --add-port=5404-5412/udp  # corosync
firewall-cmd --reload
Table 3. Table 3: TSA-MP and RSCT port usage
Service name Port number Protocols
cthats 123473 UDP
cthags 123483 UDP
rmc 6574 UDP
rmc 6574 TCP
Note:
  1. RSCT includes Tivoli SA MP.
  2. For more details, see, RSCT port usage
  3. This port number can be customized. The default value is shown.
  4. This port number is not configurable.