Mini Core Dumps; Enabling Tcp Dumps - Dell Force10 Z9000 Configuration Manual

To undo this command, use the no logging coredump server command.

Mini Core Dumps

Dell Networking OS supports mini core dumps for kernel crashes. The mini core dump applies to Master units.
Kernel mini core dumps are always enabled. The mini core dumps contain the stack space and some other very minimal information
that can be used to debug a crash. These files are small files and are written into flash until space is exhausted. When the flash is full,
the write process is stopped.
A mini core dump contains critical information in the event of a crash. Mini core dump files are located in flash://CORE_DUMP_DIR
directory. The kernel mini core filename format is f10StkUnit<stack_unit_no>.kcore.mini.txt.
The panic string contains key information regarding the crash. Several panic string types exist, and they are displayed in regular
english text to enable easier understanding of the crash cause.
Example of a Mini Core Text File
VALID MAGIC
------------------------PANIC STRING -----------------
panic string is : <null>
----------------------STACK TRACE START---------------
0035d60c <f10_save_mmu+0x120>:
00274f8c <panic+0x144>:
0024e2b0 <db_fncall+0x134>:
0024dee8 <db_command+0x258>:
0024d9c4 <db_command_loop+0xc4>:
002522b0 <db_trap+0x158>:
0026a8d0 <mi_switch+0x1b0>:
0026a00c <bpendtsleep>:
------------------------STACK TRACE END----------------
---------------------------FREE MEMORY---------------
uvmexp.free = 0x2312

Enabling TCP Dumps

TCP dump captures CPU bound control plane traffic to improve troubleshooting and system manageability.
When you enable TCP dumps, a dump captures all the packets on the local CPU, as specified in the CLI.
You can save the traffic capture files to flash, to FTP, SCP, or TFTP. The files saved on the flash are located in the flash://
TCP_DUMP_DIR/Tcpdump_<time_stamp_dir>/ directory and are labeled tcpdump_*.pcap. There can be up to 20
tcpdump_<time_stamp_dir> directories. The file after 20 overwrites the oldest saved file. The maximum file size for a TCP dump
capture is 1MB. When a file reaches 1MB, a new file is created, up to the specified total number of files.
Maximize the number of packets recorded in a file by specifying the snap-length to capture the file headers only.
The tcpdump command has a finite run process. When you enable the command, it runs until the capture-duration timer and/or the
packet-count counter threshold is met. If you do not set a threshold, the system uses a default of 5 minute capture-duration and/or
a single 1k file as the stopping point for the dump.
You can use the capture-duration timer and the packet-count counter at the same time. The TCP dump stops when the first of the
thresholds are met. That means that even if the duration timer is 9000 seconds, if the maximum file count parameter is met first, the
dumps stop.
• Enable a TCP dump for CPU bound traffic.
CONFIGURATION mode
tcpdump cp [capture-duration time | filter expression | max-file-count value | packet-
count value | snap-length value | write-to path]
Z-Series Debugging and Diagnostics
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