Filter
Top Products
17-2
Cisco 10000 Series Router Software Configuration Guide
OL-2226-23
Chapter 17 Cisco 10000 Series Router PXF Stall Monitor
Information about Cisco 10000 Series Router PXF Stall Monitor
• PXF stall—On the LC to PXF path, shown in Figure 17-1, if there are no packets passing between
Cobalt3 and the PXF, the PXF stalls. The stall occurs when a packet is not completely read from the
Internal Packet Memory (IPM); therefore, the entry remains in the Cobalt3 New Work Queue
(NWQ). This entry is marked as the top entry and stays there. To avoid the stall, there is a 24-bit
counter in Cobalt3 NWQ that counts the number of clock ticks outstanding for the top entry of each
Cobalt3 NWQ. When the programmable threshold is reached, an event is generated to RP that
reloads the PXF.
• Ironbus (IB) stuck pause request—On the PXF to LC path, shown in Figure 17-2, an IB Stuck Pause
Request error is detected by the Nickel driver. This error occurs when the LC egress data path does
not function correctly. When this error occurs the Nickel driver restarts the Iron Bus. If the error
repeats from the same LC within 4 seconds, the entire LC is reloaded.
• Control path—The RP and LCs are connected on the Backplane Ethernet (BPE). Through BPE, the
RP monitors the condition of the LCs, using keepalives packets that are sent every second from the
LCs to RP. If the keepalives packet does not reach RP on time, the corresponding LC gets reloaded.
Figure 17-1 Data Path - LC to PXF
Figure 17-2 Data Path - PXF to LC/RP
In certain cases, the PSM detects stalls due to failures in the following data flow paths:
LC
PXF
Backplane
Iron Bus Iron Bus SPI-DP
Cobalt3
Nickel
BP
277388
Vanadium/
.Barium/Nickel
10G
LC
Vanadium/
.Barium/Nickel
10G
RP
PXF
Backplane
Iron Bus Iron Bus SPI-DP
Cobalt3
Nickel
BP
BP
HTDP
BP = Back pressure
277389