1. The applicable order and scheme are as follows:
"Remote Connect and Execute command"
SSH-P22 [email protected]
SSH-P22 [email protected] /sbin/ifconfig
"Remote copy: Push and Pull"
Scp-p22-r-p/etc [email protected]:/tmp/
Scp-p22-r-P [email protected]:/tmp//etc
"Secure FTP Feature"
sftp-oport=22 [email protected]
"No Password Authentication scheme"
For example, use Sshkey to bulk distribute files and perform deployment operations.
2, the main reason for the slow connection is that DNS resolution causes
Workaround:
1. On the SSH server, change the configuration in the/etc/ssh/sshd_config file to the following:
Usedns no
# GSSAPI options
Gssapiauthentication no
Then, Performing/etc/init.d/sshd Restart Restart the sshd process so that the above configuration takes effect, the connection is generally not slow.
2, if it is slow, check the SSH server on the/etc/hosts file, 127.0.0.1 the corresponding hostname is the same as
Uname-n results, or the native IP and hostname (uname-n result) into/etc/ In the hosts.
12345678 |
[root @C64 ~] # Uname-n c64 [root @C64 ~] # cat/etc/hosts #modi by Oldboy 11:12 2013/9/24 127.0.0.1 C64 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost Localhost.localdomain localhost6 localhost6.localdomain6 10.0.0.18 C64 ################ |
3, the use of Ssh-v debugging function to find the cause of slow
In fact, you can use the following command to debug why the slow details (learning this idea is very important).
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465 6667686970717273747576777879808182 |
[root
@C64
~]
# ssh -v [email protected]
OpenSSH_5.3p1, OpenSSL 1.0.0-fips 29 Mar 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options
for
*
debug1: Connecting to 10.0.0.19 [10.0.0.19] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type -1
debug1: identity file /root/.ssh/id_dsa type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH_4*
debug1: Enabling compatibility mode
for
protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
The authenticity of host
‘10.0.0.19 (10.0.0.19)‘ can
‘t be established.
RSA key fingerprint is ca:18:42:76:0e:5a:1c:7d:ef:fc:24:75:80:11:ad:f9.
Are you sure you want to continue connecting (yes/no)? yes
=======>老男孩老师评:这里就是提示保存密钥的交互提示。
Warning: Permanently added ‘
10.0.0.19
‘ (RSA) to the list of known hosts.
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Trying private key: /root/.ssh/identity
debug1: Trying private key: /root/.ssh/id_rsa
debug1: Trying private key: /root/.ssh/id_dsa
debug1: Next authentication method: password
[email protected]‘
s password:
=======>老男孩老师评:这里就是提示输入密码的交互提示。
debug1: Authentication succeeded (password).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = en_US.UTF-8
Last login: Tue Sep 24 10:30:02 2013 from 10.0.0.18
在远程连接时如果慢就可以确定卡在哪了。
[root
@C64_A
~]
# ssh -v [email protected]
OpenSSH_5.3p1, OpenSSL 1.0.0-fips 29 Mar 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options
for
*
debug1: Connecting to 10.0.0.17 [10.0.0.17] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type -1
debug1: identity file /root/.ssh/id_dsa type 2
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3
debug1: match: OpenSSH_5.3 pat OpenSSH*
debug1: Enabling compatibility mode
for
protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host
‘10.0.0.17‘
is known and matches the RSA host key.
debug1: Found key
in
/root/.ssh/known_hosts:2
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can
continue
: publickey,gssapi-keyex,gssapi-with-mic,password
debug1: Next authentication method: gssapi-keyex
debug1: No valid Key exchange context
debug1: Next authentication method: gssapi-with-mic
|
The above configuration does not match the discovery card to gssapi this. You probably know it's a gssapi problem.
In fact, the Linux System Optimization section should optimize the SSH service here.
Linux under SSH remote Connection service Slow solution