Description: Base address for the computation of the IP addresses for the management interfaces of the cards. When the PEMServer wants to connect to a card in the rack, it computes the card IP address from ipBaseAddress, the slot number of the card, and the systemNumber of the rack (also in pegasusSystem), as follows: the slot number is added to the last byte of ipBaseAddress, modulo 256, and the systemNumber is added to the next to last byte of ipBaseAddress, again modulo 256.

Example 1 2 3 iPBaseAddress |192.168. 0. 0|192.168.244.231|192.168. 0. 0 systemNumber | +4 | +4 | +4 slot number | +1| +3| +5 sum | 4 1| 4 234| 4 5 sum modulo 256 | 4 1| 4 234| 4 5 Resulting mgmt IP-# |192.168. 4. 1|192.168.248.234|192.168. 4. 5

The slot cards compute their own management interface IP addresses in a similar way, using their own ip base addresses. These base addresses are not visible through the PEM Client or SNMP. To read or change them on a card, the CLI must be used.

All slot cards within a PEGASUS system must have the management IP addresses in the same network in order to communicate with each other. They must then have the same base address (with the exception of biasing, as explained below). The base addresses of all cards are usually chosen such that the management IP addresses end up in a non-routable (private) networks.

Biasing: cards read slot and rack numbers through dedicated pins on their backplane plugs. If such a pin is damaged, cards read bad numbers and compute bad (possibly conflicting) IP addresses. In this case, the CLI can be used to set the base address such that the resulting address is still correct.