//本机ip:192.168.1.6[root@codfei ~]# ssh-keygen -t rsaGenerating public/private rsa key pair.Enter file in which to save the key (/root/.ssh/id_rsa):/root/.ssh/id_rsa already exists.Overwrite (y/n)? y     //以为我是第2 次建立关系所以此处覆盖原来的文件)Enter passphrase (empty for no passphrase):  //直接回车无须输入密钥)Enter same passphrase again:Your identification has been saved in /root/.ssh/id_rsa.Your public key has been saved in /root/.ssh/id_rsa.pub.The key fingerprint is:04:37:13:2a:4b:10:af:c1:2b:03:3f:6b:27:ce:b9:62 root@codfei[root@codfei ~]# cd .ssh/[root@codfei .ssh]# ll-rw------- 1 root root 883 Apr 25 17:51 id_rsa-rw-r--r-- 1 root root 221 Apr 25 17:51 id_rsa.pub-rw-r--r-- 1 root root 442 Apr 25 17:37 known_hosts

[root@codfei .ssh]# scp id_rsa.pub192.168.1.4:/root/.ssh/192.168.1.6root@192.168.1.4‘s password:id_rsa.pub 100% 221 0.2KB/s 00:00

[root@codfei ~]# cd .ssh/[root@codfei .ssh]# cat 192.168.1.6 >> authorized_keys

[root@codfei .ssh]# ssh 192.168.1.4Last login: Wed Aug 8 12:14:42 2007 from 192.168.1.6

####脚本如下########################!/bin/bash#SCRIPT:df_check.sh#Writeen by codfei Mon Sep 3 07:25:28 CST 2007#PURPOSE:This script is used to monitor for full filesystems.#######################Begining########################################FSMAX="80"remote_user=‘root‘ #####完全可以不用rootremote_ip=(192.168.1.5 192.168.1.6 192.168.1.7 192.168.1.8 192.168.1.9192.168.1.10 192.168.1.11 192.168.1.12 192.168.1.13 192.168.1.14 ) ----># 这里填写你要监控的主机ipip_num=‘0‘while [ "$ip_num" -le "$(expr ${#remote_ip[@]} - 1)" ]doread_num=‘1‘ssh "$remote_user"@"${remote_ip[$ip_num]}" df -h > /tmp/diskcheck_tmpgrep ‘^/dev/*‘ /tmp/diskcheck_tmp|awk ‘{print $5}‘|sed ‘s//%//g‘ >/tmp/diskcheck_num_tmpwhile [ "$read_num" -le $(wc -l < /tmp/diskcheck_num_tmp) ]dosize=$(sed -n "$read_num"‘p‘ /tmp/diskcheck_num_tmp)if [ "$size" -gt "$FSMAX" ]then$(grep ‘^/dev/*‘ /tmp/diskcheck_tmp|sed -n $read_num‘p‘ >/tmp/disk_check_mail)$(echo ${remote_ip[$ip_num]} >> /tmp/disk_check_mail)$(mail -s "diskcheck_alert" admin < /tmp/disk_check_mail)firead_num=$(expr $read_num + 1)doneip_num=$(expr $ip_num + 1)done#############over################################################让脚本每十分钟执行一次#############在cron 表中加入0/10 * * * * /home/codfei/diskcheck.sh 2>&1##########################################################################比如， ext2 文件系统， 如果异常死机，开机如何修复文件系统？如果异常关机，比如断电，通知机房的人开机之后，我们需要远程修复、检查文件系统除了/分区之外， 其他的分区：umount /homefsck -y /home/*/ 分区需要开机之后， 由机房的人来扫描随后我们再登录并扫描/home 等其他分区如何查看一个进程所使用的文件句柄？看这里面 /proc/进程号/fd/的个数就行了*/

#简单的比如如何查看apache 进程数[root@localhost fd]# ps -ef|grep httpd|wc -l1