CentOS 6.x一直有/etc/security/limits.d/90-nproc.conf 文件问题覆盖/etc/security/limits.conf设置问题，导致配置不生效。limit在限制的时候先读取的是90-nproc.conf ，导致limits.conf设置不生效。解决办法可以是：
1. 两个文件保持一致
2. 配置的时候依据90-nproc.conf为准
3. 删除90-nproc.conf
下来考证一下。
6.0
http://vault.centos.org/6.0/os/x86_64/Packages/pam-1.1.1-4.el6.x86_64.rpm
代码语言：javascript复制[root@VM_0_33_centos tmp]# rpm2cpio pam-1.1.1-4.el6.x86_64.rpm |cpio -div
./etc/pam.d
./etc/pam.d/config-util
./etc/pam.d/fingerprint-auth
./etc/pam.d/other
./etc/pam.d/password-auth
./etc/pam.d/smartcard-auth
./etc/pam.d/system-auth
./etc/security
./etc/security/access.conf
./etc/security/chroot.conf
./etc/security/console.apps
./etc/security/console.handlers
./etc/security/console.perms
./etc/security/console.perms.d
./etc/security/group.conf
./etc/security/limits.conf
./etc/security/limits.d
./etc/security/limits.d/90-nproc.conf << 6.1
http://vault.centos.org/6.1/os/x86_64/Packages/pam-1.1.1-8.el6.x86_64.rpm
代码语言：javascript复制[root@VM_0_33_centos tmp]# rpm2cpio pam-1.1.1-8.el6.x86_64.rpm | cpio -div
./etc/pam.d
./etc/pam.d/config-util
./etc/pam.d/fingerprint-auth
./etc/pam.d/other
./etc/pam.d/password-auth
./etc/pam.d/smartcard-auth
./etc/pam.d/system-auth
./etc/security
./etc/security/access.conf
./etc/security/chroot.conf
./etc/security/console.apps
./etc/security/console.handlers
./etc/security/console.perms
./etc/security/console.perms.d
./etc/security/group.conf
./etc/security/limits.conf
./etc/security/limits.d
./etc/security/limits.d/90-nproc.conf <<
./etc/security/namespace.conf6.10
http://mirrors.tencent.com/centos/6.10/os/x86_64/Packages/pam-1.1.1-24.el6.x86_64.rpm
代码语言：javascript复制[root@VM_0_33_centos tmp]# rpm2cpio pam-1.1.1-24.el6.x86_64.rpm | cpio -div
./etc/pam.d
./etc/pam.d/config-util
./etc/pam.d/fingerprint-auth
./etc/pam.d/other
./etc/pam.d/password-auth
./etc/pam.d/smartcard-auth
./etc/pam.d/system-auth
./etc/security
./etc/security/access.conf
./etc/security/chroot.conf
./etc/security/console.apps
./etc/security/console.handlers
./etc/security/console.perms
./etc/security/console.perms.d
./etc/security/group.conf
./etc/security/limits.conf
./etc/security/limits.d
./etc/security/limits.d/90-nproc.conf <<结论：
CentOS 6.x一直有90-nproc.conf文件问题,90-nproc.conf文件会覆盖/etc/security/limits.conf。
https://bugzilla.redhat.com/show_bug.cgi?id=919793
代码语言：shell复制Description of problem:
/etc/security/limits.d/90-nproc.conf was introduced in pam package in RH6. It contains this line:
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.
* soft nproc 1024
This line overrides the conventionally set /etc/security/limits.conf value of the same name. Years of expected behavior are thrown out the window and honest system administrators are exposed to outages on Redhat 6!<<简直人神共愤！
