IP address allocation and usage

As you plan your installation, you must consider IP address requirements and service access for the system.

Use Table 1 to consider the TCP/IP address requirements of the system and the requirements to access other services. You must also plan for the IP address allocation, and for the configuration of the Ethernet router, gateway and firewall.
Table 1. Summary of TCP/IP ports and services
Service Traffic direction Protocol Port Service type
Email (SMTP) notification and inventory reports Outbound TCP 25 Optional
SNMP event notification Outbound UDP 162 Optional
Syslog event notification Outbound
TCP
UDP
6514 (TCP)
514 (UDP)
Optional
IPv4 DHCP (Node service address) Outbound UDP 68 Optional
IPv6 DHCP (Node service address) Outbound UDP 547 Optional
Network time server (NTP) Outbound UDP 123 Optional
SSH for command line interface (CLI) access Inbound TCP 22 Mandatory
Remote support assistance Outbound TCP 22 Optional
HTTPS for GUI access Inbound TCP 443 Mandatory
Uploading support packages to IBM Outbound TCP 443 Optional
Remote support assistance for HTTPS GUI access Outbound TCP 443 Optional
CIMOM (HTTPS) Inbound TCP 5989 Optional
CIMOM SLPD Inbound UDP 427 Optional
Remote user authentication service - HTTP Outbound TCP 16310 Optional
Remote user authentication service - HTTPS Outbound TCP 16311 Optional
Remote user authentication service - Lightweight Directory Access Protocol (LDAP) Outbound TCP 389 Optional
iSCSI Inbound TCP 3260 Optional
iSCSI iSNS Outbound TCP 3260 Optional
IP-based RDMA clustering Inbound and Outbound TCP 4791, 21451, 21452, and 21455 Optional
IP-based RDMA clustering Inbound and Outbound UDP 4791, 21451, 21452, and 21455 Optional
IP Partnership management IP communication Inbound TCP 3260 Optional
IP Partnership management IP communication Outbound TCP 3260 Optional
IP Partnership data path connections Inbound TCP 3265 Optional
IP Partnership data path connections Outbound TCP 3265 Optional
REST API access and replication management Inbound and Outbound TCP 7443 Optional
NVMe over RDMA Inbound and Outbound UDP over RoCEv2 4420 Optional

For configuration and management, you must allocate an IP address to the system; this IP address is referred to as the management IP address. For extra fault tolerance, you can also configure a second IP address for the second Ethernet port on the node. The addresses must be fixed addresses. If IPv4 and IPv6 are operating concurrently, you must provide an address for each protocol.

Attention: The address for a management IP cannot be the same address that is used for the service IP. Using the same IP address causes communication problems.

Name servers are not used to locate other devices. You must supply the numeric IP address of the device. To locate a device, the device must have a fixed IP address.