Chapter 5. System management connectivity 91
5.1.1 Internal IP addresses
Some IP addresses are reserved for internal use in an IBM 2029 network (for
example, to route system management traffic from shelf to shelf using the internal
OSPF protocol flows). A breakdown of these IP addresses is shown in Table 13.
Table 13. Internal IP addresses
Note that hubbinggroup (Ethernet Hubbing Group) and shelfID (Shelf Identifier)
are set at shelf commissioning time. For a description of these values, see
“Ethernet Hubbing Group” on page 95 and “Shelf Identifier” on page 92.
5.1.2 IP addressing rules
The following rules must be applied when commissioning a shelf, to allow
communications between all shelves in the IBM 2029 network and the System
Manager and/or the External Manager.
• Each shelf in the network must have a unique IP address.
• The internal IP address range listed in Table 13 must not be used when
allocating the shelf IP addresses.
• Only one shelf in the IBM 2029 network must be defined as the primary shelf.
This shelf maintains the network management information database including
the System Manager shelf list and network tree.
• Each shelf in the network must point to the primary shelf IP address.
• Each shelf must be segmented into its own subnetwork, using a subnet mask.
The only exception to this is the GNE shelf connecting to an IP network using
the Proxy Address Resolution Protocol (ARP) function. See 5.3.3, “Connecting
via an IP Network in a single GNE environment” on page 102.
IP Address Range Details
10.0.0.x 1 to 19 Used for intershelf communications
10.0.shelfID.x 1 to 254 Used for intershelf communications
10.1.254.1 Uncommissioned shelf address
10.1.shelfID.1 IP address for 10BASE-T 1X port
10.1.shelfID.2 DHCP address for 10BASE-T 1X port
10.2.hubbinggroup.x shelfID IP address for 10BASE-T 2X port
10.2.hubbinggroup.x shelfID + 128 DHCP address for 10BASE-T 2X port
10.2.hubbinggroup.255 Broadcast address
10.3.shelfID.1 DTE local
10.3.shelfID.2 DTE remote
10.4.shelfID.1 DCE local
10.4.shelfID.2 DCE remote
If you assign any of the internal IP addresses to any shelf, communications
within the IBM 2029 network will fail.