SIGSEGV by default forces a core dump. If there is no core file the usual reason is that ulimit for the process coredump value is zero.
A setuid process may also not want to dump core.
You probably should see a file named "core" in the cwd of the process, which is often the login directory. If this is a ulimit probelm, reset ulimit to allow coredump for the user that runs the process.
does any one have read a core dump?
is there any reader for that? or may i know what is the use of that core which takes sometimes memory in GBs?
:) (6 Replies)
I've got a core dump in my weblogic home directory, which i have tried to debug by initiating savecore from /etc/init.d/savecore start
but savecore failed to create the two files, that is vmcore.n and vmunix.n.
savecore is enable on my server to save vmcore and vmunix in /var/crash/hostname
1)... (4 Replies)
Hi All,
i am new to this forum.i want detail of reading the core file and trace the problem because of what the program get crashed.please help me.if any body knows any website or tutoril plese let me know.
sudhir (6 Replies)
Hi ,
I want to read core dump file on AIX5.3. While i am trying to use following commands, i am getting only few lines of information.
ux201p3:e46123> dbx capsWrkstnMgr core
Type 'help' for help.
reading symbolic information ...
Segmentation fault in malloc_common.extend_brk at... (1 Reply)
Hello
Im using redhat and try to debug my application , its crashes and in strace I also see it has problems , but I can't see any core dump
I configured all the limit ( im using .cshrc ) and it looks like this :
cputime unlimited
filesize unlimited
datasize unlimited... (8 Replies)
Hi Guys,
I was wondering if somebody could give me a link to a very good source of information or document about core dump process and How to's about it. I have also googled it and found some articles myself.
Thanks
Messi (1 Reply)
Hi guys,
just want to know which core file pattern is best to set for core dumps:
1) per-process file name pattern
or
2) global file name pattern.
I will really appreciate an explanation why the chosen one is better.
Thanks a lot guys. (2 Replies)
Hello All,
I am new joiner of this forum.I am new to Linux shell scripting.
At present I have identified 1 application which stalls very frequently (PID is say xyz) and I am not having much information in its application log to identify the root cause of stalling. I need to take the core dump... (19 Replies)
Discussion started by: Anjan Ganguly
19 Replies
LEARN ABOUT BSD
savecore
SAVECORE(8) System Manager's Manual SAVECORE(8)NAME
savecore - save a core dump of the operating system
SYNOPSIS
savecore dirname [ system ]
DESCRIPTION
Savecore is meant to be called at the end of the /etc/rc file. Its function is to save the core dump of the system (if one was made) and
to write a reboot message in the shutdown log.
It saves the core image in the file dirname/core.n and its corresponding namelist in dirname/unix.n. The second argument is the namelist
for the system which made the core image; the current system is always assumed to be /unix. The trailing ".n" in the pathnames is replaced
by a number which grows every time savecore is run in that directory.
Before savecore writes out a core image, it reads a number from the file dirname/minfree. If there are fewer free blocks on the file sys-
tem which contains dirname than the number obtained from the minfree file, the core dump is not done. If the minfree file does not exist,
savecore always writes out the core file (assuming that a core dump was taken).
Savecore also writes a reboot message in the shut down log. If the system crashed as a result of a panic, savecore records the panic
string in the shut down log too.
If savecore detects that the system time is wrong because of a crash (the time in the core image is after the current time), it will reset
the system time to its best estimate of the time, which is the time in the core image plus the elapsed time since the reboot. It announces
the time that it set when this occurs.
FILES
/usr/adm/shutdownlogshutdown log
/unix current UNIX
BUGS
The method used to determine whether a dump is present, and to prevent the same core image from being saved multiple times, is not elegant.
This information should be passed to init by the system; however, this is difficult because the system may have to be rebooted a second
time if the root filesystem is patched.
3rd Berkeley DistributionSAVECORE(8)