| 39 | 39 | As with any substantial system project, this one has experienced a number of issues as we have gone through the system integration process. Most of these were ultimately traceable back to software bugs that did not become apparent until various system components were put together and exercised in realistic usage scenarios. For example, we have experienced a several issues relating to the Network Address Translation (NAT) module implemented in the Line Card. NAT requires coordinated activities within the Line Card data path, the NAT daemon running on the xScale and the System Resource Manager (SRM), which runs on the CP. This creates opportunities for subtle errors, which only become apparent when the system is being used. We have also experienced issues with the Shelf Manager, which provides low level control of the ATCA chassis that hosts most of the system components (for example, the shelf manager can be used to power-off or reset individual boards). These issues involve conflicting control actions by the Shelf Manager and the board that implements the chassis switch. We have worked with the vendor of the chassis switch (Radisys) to identify the problem and turn-off the software component on the chassis switch that causes the problem, but do not yet have a satisfactory resolution. Issues of this sort consume time and effort, but we are working through them and expect to have most, if not all of them, resolved over the next few months. |
