hadoop配置 - ssh-copy-id with port

使用下例中ssky-keygen和ssh-copy-id，仅需通过3个步骤的简单设置而无需输入密码就能登录远程Linux主机。 

ssh-keygen 创建公钥和密钥。 

ssh-copy-id 把本地主机的公钥复制到远程主机的authorized_keys文件上。

ssh-copy-id 也会给远程主机的用户主目录（home）和~/.ssh, 和~/.ssh/authorized_keys设置合适的权限 。

步骤1: 用 ssh-key-gen 在本地主机上创建公钥和密钥

ligh@local-host$ ssh-keygen -t  rsa
Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key]
Enter passphrase (empty for no passphrase): [Press enter key]
Enter same passphrase again: [Pess enter key]
Your identification has been saved in /home/jsmith/.ssh/id_rsa.
Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub.
The key fingerprint is: 33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9

ligh@local-host

步骤1.5:把公钥复制到本机上

ligh@local-host$ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

[注:把密钥追加到本机的 .ssh/authorized_key 上.]

步骤2: 用 ssh-copy-id 把公钥复制到远程主机上

ligh@local-host$ ssh-copy-id -i ~/.ssh/id_rsa.pub  root@192.168.0.3
ligh@remote-host‘s password:
Now try logging into the machine, with ―ssh ?remote-host‘‖, and check in:
.ssh/authorized_keys to make sure we haven‘t added extra keys that you weren‘t expecting.

[注: ssh-copy-id 把密钥追加到远程主机的 .ssh/authorized_key 上.]

步骤3: 直接登录远程主机

ligh@local-host$ ssh remote-host
Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2
ligh@remote-host$

[注: SSH 不会询问密码.]

补充：

cat ssh-copy-id

#!/bin/sh

# Shell script to install your identity.pub on a remote machine
# Takes the remote machine name as an argument.
# Obviously, the remote machine must accept password authentication,
# or one of the other keys in your ssh-agent, for this to work.

ID_FILE="${HOME}/.ssh/identity.pub"

while getopts ':i:p:P:h' OPTION
do
case $OPTION in
i)
if [-n"$OPTARG"]; then
if expr "$OPTARG" : ".*.pub" > /dev/null ; then
ID_FILE="$OPTARG"
else
ID_FILE="$OPTARG.pub"
fi
fi
;;
P|p)
PORT=$OPTARG;
;;
h)
echo "Usage: $0 [-i [identity_file]] [user@]machine">&2
exit 1
;;
esac;
done;

shift $(($OPTIND- 1))

if [ $# -lt 1 ] && [ x$SSH_AUTH_SOCK != x ] ; then
GET_ID="$GET_ID ssh-add -L"
fi

if [ -z "`eval $GET_ID`" ] &&[-r"${ID_FILE}"]; then
GET_ID="cat ${ID_FILE}"
fi

if [ -z "`eval $GET_ID`" ]; then
echo "$0: ERROR: No identities found" >&2
exit 1
fi

if [ -z $PORT]; then
PORTOPTION=""
else
PORTOPTION="-p $PORT "
fi;

{ eval "$GET_ID" ; } | ssh $PORTOPTION$1"umask 077; test -d .ssh || mkdir .ssh ; cat >> .ssh/authorized_keys"||exit 1

cat <<EOF
Now try logging into the machine, with "ssh $PORTOPTION'$1'", and check in:

.ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

EOF

# ssh-copy-id -i ~/.ssh/id_rsa.pub "-p 22222
user@server"