1、现象： 使用crt连接服务器的速度很慢， 使用x$shell连接的速度却很快
2、解决思路：
打开securecrt的file--->trace options，点选后， 直接连接服务器，查看输出的trace信息，
可以看到如下信息：
[PRINTER] : Printer initialization succeeded
[LOCAL] : SSH2Core version 8.5.0.1740
[LOCAL] : Connecting to 10.2.130.230:22 ...
[LOCAL] : Changing state from STATE_NOT_CONNECTED to STATE_EXPECT_KEX_INIT
[LOCAL] : Using protocol SSH2
[LOCAL] : RECV : Remote Identifier = 'SSH-2.0-OpenSSH_5.3'
[LOCAL] : CAP : Remote can re-key
[LOCAL] : CAP : Remote sends language in password change requests
[LOCAL] : CAP : Remote sends algorithm name in PK_OK packets
[LOCAL] : CAP : Remote sends algorithm name in public key packets
[LOCAL] : CAP : Remote sends algorithm name in signatures
[LOCAL] : CAP : Remote sends error text in open failure packets
[LOCAL] : CAP : Remote sends name in service accept packets
[LOCAL] : CAP : Remote includes port number in x11 open packets
[LOCAL] : CAP : Remote uses 160 bit keys for SHA1 MAC
[LOCAL] : CAP : Remote supports new diffie-hellman group exchange messages
[LOCAL] : CAP : Remote correctly handles unknown SFTP extensions
[LOCAL] : CAP : Remote correctly encodes OID for gssapi
[LOCAL] : CAP : Remote correctly uses connected addresses in forwarded-tcpip requests
[LOCAL] : CAP : Remote can do SFTP version 4
[LOCAL] : CAP : Remote uses SHA1 hash in RSA signatures for x.509v3
[LOCAL] : CAP : Remote x.509v3 uses ASN.1 encoding for DSA signatures
[LOCAL] : CAP : Remote correctly handles zlib@openssh.com
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [Kerberos] SPN : host@10.2.130.230
SecureCRT - Version 8.5.0 (x64 build 1740)
[LOCAL] : GSS : [Kerberos] InitializeSecurityContext() failed.
[LOCAL] : GSS : [Kerberos] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [Kerberos] Disabling gss mechanism
[LOCAL] : GSS : [Kerberos] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-group1-sha1-toWM5Slw5Ew8Mqkay+al2g==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [Kerberos (Group Exchange)] SPN : host@10.2.130.230
[LOCAL] : GSS : [Kerberos (Group Exchange)] InitializeSecurityContext() failed.
[LOCAL] : GSS : [Kerberos (Group Exchange)] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [Kerberos (Group Exchange)] Disabling gss mechanism
[LOCAL] : GSS : [Kerberos (Group Exchange)] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.3.5.1.5.2] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.3.5.1.5.2] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.3.5.1.5.2] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [1.3.5.1.5.2] Disabling gss mechanism
[LOCAL] : GSS : [1.3.5.1.5.2] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-group1-sha1-A/vxljAEU54gt9a48EiANQ==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.3.5.1.5.2 (Group Exchange)] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.3.5.1.5.2 (Group Exchange)] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.3.5.1.5.2 (Group Exchange)] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [1.3.5.1.5.2 (Group Exchange)] Disabling gss mechanism
[LOCAL] : GSS : [1.3.5.1.5.2 (Group Exchange)] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-gex-sha1-A/vxljAEU54gt9a48EiANQ==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.2.840.48018.1.2.2] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.2.840.48018.1.2.2] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.2.840.48018.1.2.2] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
gss_display_status() failed: uMinorCode = 100006
[LOCAL] : GSS : [1.2.840.48018.1.2.2] Disabling gss mechanism
[LOCAL] : GSS : [1.2.840.48018.1.2.2] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-group1-sha1-bontcUwnM6aGfWCP21alxQ==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.2.840.48018.1.2.2 (Group Exchange)] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.2.840.48018.1.2.2 (Group Exchange)] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.2.840.48018.1.2.2 (Group Exchange)] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
gss_display_status() failed: uMinorCode = 100006
[LOCAL] : GSS : [1.2.840.48018.1.2.2 (Group Exchange)] Disabling gss mechanism
[LOCAL] : GSS : [1.2.840.48018.1.2.2 (Group Exchange)] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-gex-sha1-bontcUwnM6aGfWCP21alxQ==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.3.6.1.5.2.5] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.3.6.1.5.2.5] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.3.6.1.5.2.5] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [1.3.6.1.5.2.5] Disabling gss mechanism
[LOCAL] : GSS : [1.3.6.1.5.2.5] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-group1-sha1-eipGX3TCiQSrx573bT1o1Q==
[LOCAL] : GSS : Requesting full delegation
[LOCAL] : GSS : [1.3.6.1.5.2.5 (Group Exchange)] SPN : host@10.2.130.230
[LOCAL] : GSS : [1.3.6.1.5.2.5 (Group Exchange)] InitializeSecurityContext() failed.
[LOCAL] : GSS : [1.3.6.1.5.2.5 (Group Exchange)] The gssapi provider indicated a failure. Unspecified GSS failure. Minor code may provide more information
Internal credentials cache error
[LOCAL] : GSS : [1.3.6.1.5.2.5 (Group Exchange)] Disabling gss mechanism
[LOCAL] : GSS : [1.3.6.1.5.2.5 (Group Exchange)] Disabling gss mechanism
[LOCAL] : The following key exchange method has been filtered from the key exchange method list because it is not supported: gss-gex-sha1-eipGX3TCiQSrx573bT1o1Q==
[LOCAL] : SEND : KEXINIT
[LOCAL] : RECV : Read kexinit
[LOCAL] : Available Remote Kex Methods = diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
[LOCAL] : Selected Kex Method = diffie-hellman-group14-sha1
[LOCAL] : Available Remote Host Key Algos = ssh-rsa,ssh-dss
[LOCAL] : Selected Host Key Algo = ssh-rsa
[LOCAL] : Available Remote Send Ciphers = aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
[LOCAL] : Selected Send Cipher = aes256-ctr
[LOCAL] : Available Remote Recv Ciphers = aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
[LOCAL] : Selected Recv Cipher = aes256-ctr
[LOCAL] : Available Remote Send Macs = hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
[LOCAL] : Selected Send Mac = hmac-sha2-512
[LOCAL] : Available Remote Recv Macs = hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
[LOCAL] : Selected Recv Mac = hmac-sha2-512
[LOCAL] : Available Remote Compressors = none,zlib@openssh.com
[LOCAL] : Selected Compressor = none
[LOCAL] : Available Remote Decompressors = none,zlib@openssh.com
[LOCAL] : Selected Decompressor = none
[LOCAL] : Changing state from STATE_EXPECT_KEX_INIT to STATE_KEY_EXCHANGE
[LOCAL] : SEND : KEXDH_INIT
[LOCAL] : RECV : KEXDH_REPLY
[LOCAL] : Changing state from STATE_KEY_EXCHANGE to STATE_READY_FOR_NEW_KEYS
[LOCAL] : RECV: Remote Hostkey (SHA-2 hash hex): 94:5a:5a:b9:e3:f1:65:6a:68:00:e0:b8:20:15:0b:2e:53:85:da:bd:39:b3:e1:2f:cd:5c:b3:14:bb:4f:83:75
[LOCAL] : RECV: Remote Hostkey (SHA-2 hash base64): lFpauePxZWpoAOC4IBULLlOF2r05s+EvzVyzFLtPg3U
[LOCAL] : RECV: Remote Hostkey (SHA-1 hash): 20:d4:98:e8:1b:3a:4d:0d:05:26:1b:08:cb:75:35:07:15:e9:db:44
[LOCAL] : RECV: Remote Hostkey (MD5 hash): 30:29:a7:ba:b0:1b:05:5e:6c:7f:8c:21:48:67:05:6d
[LOCAL] : SEND : NEWKEYS
[LOCAL] : Changing state from STATE_READY_FOR_NEW_KEYS to STATE_EXPECT_NEWKEYS
[LOCAL] : RECV : NEWKEYS
[LOCAL] : Changing state from STATE_EXPECT_NEWKEYS to STATE_CONNECTION
[LOCAL] : SEND: SERVICE_REQUEST[ssh-userauth]
[LOCAL] : RECV: SERVICE_ACCEPT[ssh-userauth] -- OK
[LOCAL] : SENT : USERAUTH_REQUEST [none]
[LOCAL] : Authenticating as user weblogic
[LOCAL] : RECV : USERAUTH_FAILURE, continuations [publickey,password]
[LOCAL] : SENT : USERAUTH_REQUEST [password]
[LOCAL] : RECV : AUTH_SUCCESS
[LOCAL] : SEND[0]: SSH_MSG_CHANNEL_OPEN('session')
[LOCAL] : SEND[0]: Pty Request (rows: 56, cols: 144)
[LOCAL] : RECV[0]: pty request succeeded
[LOCAL] : SEND[0]: shell request
[LOCAL] : RECV[0]: shell request succeeded3、分析
可以看到有很多的 key exchange method是不支持的， 所以要尽快的连接，需要将不支持的选项禁用（此处没有过多的深入研究，如何支持这些报错的 key exchange method），如下图：
全局（all sessions）后重启crt，即可以实现快速连接。问题得到解决。
有时间的朋友可以去研究下如何支持报错的key change method
