05-20-2014
If there was any such thing as ideal limits, the system would be locked into using the ideal limits and there would be no adjustment you could make. That said, a couple of issues do come to mind...
I do not like nproc to be unlimited. If someone does a while(1) fork(); I would like to be able to recover without a reboot.
We are required to justify every instance of core being any value other than 0. This is a security concern. A core file can contain information that should not be exposed. And assuming that the address space is also unlimited core files can consume lots of disk space. When a filesystem runs out of space one of the first things that admins look for are core files. Settings core to zero prevents the problem. Developers often need core files... so be it. But our default state is no core files and then we enable core files where we must.
This User Gave Thanks to Perderabo For This Post:
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
As a regular (non-root) user on Unix servers I'm accustomed to changing my .profile file to set paths that I frequently use, etc.
I am trying to learn unix and set up a test server running SunOS 5.8. When I login as root I don't see a .profile file that belongs to root wherein I could change the... (1 Reply)
Discussion started by: FredSmith
1 Replies
2. AIX
how to set the ulimit on AIX 5.2 version? (3 Replies)
Discussion started by: Shilpi
3 Replies
3. AIX
Hi all,
I cannt use 'su' to login to root or any other users though everything seems ok. I read some articles that says if you do recursive chmod 777 on /usr it can create this problem.
I did the same. can anybody tell me how to repair it. Any ideas will be appreciated.
thnks (7 Replies)
Discussion started by: itesh.dash
7 Replies
4. AIX
Hello,
How can I setup the ulimit for memory permanent
ulimit -m unlimited
ulimit -a Output from the ulimit command should be similar to the following:time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 2097152
stack(kbytes) 32768... (4 Replies)
Discussion started by: filosophizer
4 Replies
5. AIX
How to block the root user login in system direct console. Users should login with non-root ids themselves and then use the su command to become root. Which configuration file i need to check and disable it. (5 Replies)
Discussion started by: kmvinay
5 Replies
6. AIX
Hi,
I'm newbee to AIX and would like to setup a process which kills 1 Hr. ideal users from smit. Please advise for making it work. :)
Thanks,
Sumit (2 Replies)
Discussion started by: sumit30
2 Replies
7. UNIX for Dummies Questions & Answers
I've been through many threads before i decide to create a separate thread.
I can't really find the solution to my (simple) problem.
Here's what I'm trying to achieve:
As "canar" user I want to run a command, let's say "/opt/ocaml/bin/ocaml" as "duck" user.
The only to achieve this is to... (1 Reply)
Discussion started by: canar
1 Replies
8. Red Hat
The root user runs the following
ulimit -a | grep open
and gets a result of
open files (-n) 8162
A user runs the same command and gets a result of
open files (-n) 2500
How can you set the ulimit of the user to... (2 Replies)
Discussion started by: jsanders
2 Replies
9. AIX
Hello,
I am testing sudo and I want to test it. Can anyone please let me know few commands (of course other than shutdown, reboot etc. as I can't reboot the box) on AIX that can be run by ROOT only.
Thanks
---------- Post updated at 07:43 PM ---------- Previous update was at 07:38 PM... (5 Replies)
Discussion started by: prvnrk
5 Replies
10. UNIX for Advanced & Expert Users
I have seen two different ways for changing the ulimit for a user in aix. Which one is better?
Option 1
edit /etc/security/limits
oracle:
fsize = -1
data = -1
stack = -1
fsize_hard = -1
nofiles = -1
nofiles_hard = -1
Option 2
... (6 Replies)
Discussion started by: cokedude
6 Replies
coreadm(2) System Calls Manual coreadm(2)
NAME
coreadm - application core file administration
SYNOPSIS
DESCRIPTION
system call is used to specify the location and pattern for core files produced by abnormally terminating processes. See core(4). This
system call can be used to specify a system wide location for core file placement and/or a process specific pattern.
The structure, is used to specify a system wide or a per-process core file pattern and also specify the current system wide core file set-
tings. is defined in the header
Member Type Member Name Description
char c_pattern The core file pattern.
uint64_t c_flags Core file settings.
Parameters
is expected to be set to It is critical for future backward compatibility that the macro itself be used and not its value.
is the core file pattern. A core file name pattern is a normal file system path name with embedded variables, specified with a leading
character, that are expanded from values in effect when a core file is generated by the operating system. An expanded pattern length
greater than will be truncated to
The possible values are:
c_flags is used to control the system wide core file settings. The flag values can be combination of
Enable/Disable creation of global core files.
Enable/Disable creation of per-process core files.
Enable/Disable creation of global core files for
processes.
Enable/Disable creation of per-process core file for
processes.
If a flag value is not set, then the option is disabled.
For per-process core file setting, c_flags can either be 0 or The former disables core file creation (for that process) and the latter
enables it.
c_pid Should be a (valid) pid of a target process or 0. If c_pid is zero, then the settings are applied to global core file settings.
If c_pid is 1, then the settings are applied to init(1M).
c_in If non-NULL, then the values will be used as new core file settings. If this is NULL, then the c_out parameter is expected to be
non-NULL and system call is used to interrogate the current settings.
c_out If non-NULL, the current settings are returned in this parameter.
RETURN VALUE
Upon successful completion, returns 0. Otherwise, a value of -1 is returned and is set to indicate the error.
ERRORS
fails and does not change the core file settings if
the effective user-ID of the calling process is not a user having appropriate privileges.
The input or output parameter passed to
is an invalid address.
The core file pattern or flags is invalid.
The specified PID is non-zero and does not exist.
EXAMPLES
1. Enable global core file creation using the pattern (core.process-ID.machine-name) in the location
2. Enable per-process core file pattern for the process-ID passed in as argument. The core file will be placed in The pattern is
(core.process-ID.time-stamp).
3. Enable a per-process pattern of core.CUP-ID for all processes in the system (init(1M) core file setting). NOTE: This has to be run
during system startup or reboot the machine after setting this for the settings to take full effect.
SEE ALSO
coreadm(1M), exec(2), fork(2), pstat(2), ttrace(2), core(4).
STANDARDS CONFORMANCE
coreadm(2)