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The WWNN / WWPN values are derived by the seed value on the PUK card. Therefore, when changing the MPU2 card to a PUA/PUA2 card the WWNN will be the same as the MPU2 card. The WWPN will remain the same for port 1. For the second port, it depends on if the card is a PUA or a PUA2. PUA will increment by 2, PUA2 will increment by 1.