Hi all, We have been using the CentOS kexec (currently 2.0.0) as our recovery plan for kernel panic, up to now only dumping the dmesg. Since we are using a server with a large amount of RAM, we are reluctant to perform a full memory dump, both in terms of the time it will take to return from the crash kernel, and in terms of disk space reservation. Recently we where in need of a tweak to kexec so that one of our journals will be able to be saved when there is a kernel panic. I implemented what I call a "raw PFN dump" which receives as input a file containing physical frames, and their contiguous length, and will dump this "scatter gather" as raw data. This allows us to perform the following cycle: 1. Setup the journal 2. Get the physical memory mappings (using /proc/<self ot PID>/maps and /proc/<self or PID>/pagemap). 3. Format the physical memory mappings to a list of "PFN range" file 4. Add the file to the kdump.conf in the extra_bins 5. restart the kdump service 6. Activate the journal I have tested this numerous times with CentOS6.4 and kexec-tools2.0.0 (with makedumpfile 1.3.5). Would you be interested in this feature for kdump? If so, over which version should I rebase the patch? Shahar
