linux 系统环境设置
yum--update 服务停止
/sbin/service yum-updatesd status
/sbin/service yum-updatesd stop
/sbin/chkconfig --list
/sbin/chkconfig -----level yum-updatesd 2345 off
设置hostname
vi /etc/sysconfig/network
hostname server20
设置DNS
ivi /etc/resolv.conf
设置ip
setup
重启网络服务
service network restart
查看网卡情况
ip addr
参考: http://www.cnitblog.com/201/archive/2009/08/20/60887.html
创建用户
groupadd admin
useradd -m -g admin admin
userdel -fr admin
sudo 免输入密码
需要root权限
vi /etc/sudoers
在
# User privilege specification
root ALL=(ALL:ALL) ALL
后面一行新增admin ALL=(ALL) NOPASSWD :ALL
配置ssh
1.ssh-******
2. cp id_rsa authorized_keys (目的是保证authorized_keys的权限一致)
3. vi authorized_keys
4. vi /etc/ssh/sshd_config
设置下面的选项:
Port 2209
PermitRootLogin no
UseDNS no
PasswordAuthentication no
GSSAPIAuthentication no #此项默认为yes,默认登录很慢
5. /etc/init.d/sshd restart
配置limit
/etc/security/limits.conf
# End of file 一行后:
admin soft nofile 65535
admin hard nofile 65535
配置limit系统内核
vi /etc/sysctl.conf
sudo /sbin/sysctl -p 生效
#kernel.shmall = 4294967296 一行后新增:
net.core.wmem_max=12582912
net.core.rmem_max=12582912
net.ipv4.tcp_rmem= 10240 87380 12582912
net.ipv4.tcp_wmem= 10240 87380 12582912
net.ipv4.tcp_mem= 10240 87380 12582912
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_sack = 0
net.ipv4.tcp_fack = 1
net.ipv4.tcp_no_metrics_save = 1
net.core.netdev_max_backlog = 262144
net.core.somaxconn = 262144
net.ipv4.tcp_fin_timeout = 8
net.ipv4.tcp_keepalive_intvl = 20
net.ipv4.tcp_keepalive_probes = 5
net.ipv4.tcp_keepalive_time = 20
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 0
net.ipv4.ip_local_port_range = 32768 65535
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_max_tw_buckets = 1000
net.ipv4.tcp_max_orphans = 262144
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_fin_timeout = 1
net.core.somaxconn=131072
fs.file-max=3224775
注意 :内核2.6.32需要修改ulimit 中的max user processes(参考:http://blog.yufeng.info/archives/2568)
[[email protected] app]$ ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 192090
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) unlimited
open files (-n) 65535
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 192090
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
- 修改 /etc/security/limits.d/90-nproc.conf ,把默认的1024修改为unlimited
* soft nproc unlimited
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