Dell Force10 E1200i FTOS Version 8.4.1.5 Configuration Guide for ExaScale - Page 385

Software Resiliency During normal operations FTOS monitors the health of both hardware and software components in the background to identify potential failures, even before these failures manifest. Runtime System Health Check e Runtime System Health Check is supported on platform: FTOS runs a system health check to detect data transfer errors within the system. FTOS performs the check during normal operation by interspersing among, test frames among the data frames that carry user and system data. One such check is a data plane loopback test. There are some differences between the TeraScale and ExaScale line card and RPM testing: • The TeraScale card test contains a loopback from the RPM to the SFM and a loopback from the line cards to the SFM. • The ExaScale card test contains a loopback from the RPM to the SFM and a loopback from the line cards to the on-board TSF3. • For TeraScale, each line card and RPM periodically sends out test frames that loop back through the SFM. The loopback health check determines the overall status of the backplane and can identifies a faulty SFM. If three consecutive RPM loopbacks fail, then the software initiates a fault isolation procedure that sequentially disables one SFM at a time and performs the same loopback test. • For ExaScale, the RPM alone RPM periodically sends out test frames that loop back through the SFM. The loopback health check determines the overall status of the backplane and can identifies a faulty SFM. If three consecutive RPM loopbacks fail, then the software initiates a fault isolation procedure that sequentially disables one SFM at a time and performs the same loopback test. Refer to the Chapter 62, E-Series TeraScale Debugging and Diagnostics and Chapter 63, E-Series ExaScale Debugging and Diagnostics chapters for details on the different system checks performed. SFM Channel Monitoring e PCDFO is supported only on platform: Another test that is used to check the integrity of the data plane is a Per-channel De-skew FIFO Overflow (PCDFO). Each ingress and egress Buffer and Traffic Manager (BTM/FPTM) maintains nine channel connections to the SFM. The PCDFO test detects a faulty channel on an SFM, RPM, or line card by creating a test frame and striping it across all nine SFM channels between the eBTM/eFPTM and iBTM/ iFPTM. The eBTM/eFPTM must receive each segment of striped data within a specified time to be considered to have proper temporal alignment. Small skews less than the specified time are tolerated because of buffering within the BTM/FPTM. If segments are not received within the specified time, the fault is not tolerated, and FTOS initiates additional tests to isolate the fault. High Availability | 385