问题
I added to my system-wide /etc/security/limits.conf the following two rows:
* soft rtprio 55
* hard rtprio 55
After a system reboot, I get two different results according to the way I access my user account on the machine.
user@client# ssh user@server
user@server# ulimit -r
55
Then I logout and login again as root
user@client# ssh root@server
root@server# su - user
user@server# ulimit -r
0
I have no special settings neither in .bashrc nor in any other places, or, at least, I think so.
Why is this happening?
回答1:
You must look at the PAM configuration of ssh and su. I suppose that they are not the same.
For example at my system:
$ grep limit /etc/pam.d/su
# Sets up user limits, please uncomment and read /etc/security/limits.conf
# (Replaces the use of /etc/limits in old login)
# session required pam_limits.so
$ grep limit /etc/pam.d/sshd
# access limits that are hard to express in sshd_config.
# Set up user limits from /etc/security/limits.conf.
session required pam_limits.so
As you can see in one of the cases the pam_limits line is commented. I suppose that you have something like this also.
来源：https://stackoverflow.com/questions/11291307/different-values-returned-by-ulimit-r