简介
本文档介绍如何解决安全管理设备(SMA)和邮件安全设备(ESA)集成故障导致的错误：“（3，‘找不到匹配的密钥交换算法。’）或‘连接时意外EOF’和其他症状。
背景信息
SMA与ESA的连接在首次集成时，SMA为ESA提供以下密码/密钥交换算法：
kex_algorithms string: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521
encryption_algorithms_client_to_server string: aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se
encryption_algorithms_server_to_client string: aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se
建立SMA和ESA连接后，SMA为ESA提供以下密码/密钥交换算法：
kex_algorithms string: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
encryption_algorithms_client_to_server string [truncated]: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
encryption_algorithms_server_to_client string [truncated]: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
本文档中的信息都是基于特定实验室环境中的设备编写的。本文档中使用的所有设备最初均采用原始（默认）配置。如果您的网络处于活动状态，请确保您了解所有命令的潜在影响。
问题
当从GUI > Management Appliance > Centralized Services > Security Appliances或CLI > appliance将SMA集成到ESA中时，存在此问题。此问题将在连接时提示错误，这是因为ESA缺少某些kex算法/加密算法。
1. (3, 'Could not find matching key exchange algorithm.')
2. Error — Unexpected EOF on connect.
解决方案
要解决此问题，需要将ESA ssh密码配置恢复为提供的默认值：
lab.esa.com> sshconfig
Choose the operation you want to perform:
- SSHD - Edit SSH server settings.
- USERKEY - Edit SSH User Key settings
- ACCESS CONTROL - Edit SSH whitelist/blacklist
[]> sshd
ssh server config settings:
Public Key Authentication Algorithms:
rsa1
ssh-dss
ssh-rsa
Cipher Algorithms:
aes128-ctr
aes192-ctr
aes256-ctr
aes128-cbc
3des-cbc
blowfish-cbc
cast128-cbc
aes192-cbc
aes256-cbc
rijndael-cbc@lysator.liu.se
MAC Methods:
hmac-md5
hmac-sha1
umac-64@openssh.com
hmac-ripemd160
hmac-ripemd160@openssh.com
hmac-sha1-96
hmac-md5-96
Minimum Server Key Size:
1024
KEX Algorithms:
diffie-hellman-group-exchange-sha256
diffie-hellman-group-exchange-sha1
diffie-hellman-group14-sha1
diffie-hellman-group1-sha1
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
分步设置中CLI > sshconfig > sshd的输出：
[]> setup
Enter the Public Key Authentication Algorithms do you want to use
[rsa1,ssh-dss,ssh-rsa]>
Enter the Cipher Algorithms do you want to use
[aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se]>
Enter the MAC Methods do you want to use
[hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96]>
Enter the Minimum Server Key Size do you want to use
[1024]>
Enter the KEX Algorithms do you want to use
[diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521]>
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