所有虚拟机的ssh连接无反应

虚拟网络编辑器还原默认设置

ssh连接ubuntu错误。

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@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @ 
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IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! 
Someone could be eavesdropping on you right now (man-in-the-middle attack)! 
It is also possible that a host key has just been changed. 
The fingerprint for the ECDSA key sent by the remote host is 
SHA256:9XvufSSIeZ7MAurIZ1Qw9Z13YV1Zcim2kthmAlECgYw. 
Please contact your system administrator. 
Add correct host key in /root/.ssh/known_hosts to get rid of this message. 
Offending ECDSA key in /root/.ssh/known_hosts:8 
ECDSA host key for 192.168.122.100 has changed and you have requested strict checking. 
Host key verification failed. 
lost connection 

guest:
$ rm -rf ~/.ssh/known_hosts
host:
$ ssh-keygen -R 客户端IP

pwntools asm错误

需要指定系统架构。
context(os=‘linux’, arch=‘amd64’, log_level=‘debug’)

Temporary failure resolving 'mirrors.ustc.edu.cn

$ vim /etc/resolv.conf 修改DNS后重启即可
nameserver 127.0.1.1
nameserver 192.168.23.1
nameserver 221.130.33.52
nameserver 169.95.1.1
nameserver 114.114.114.114

error while loading shared libraries: libstdc++.so.6: cannot open shared object file: No such file or directory

$ apt install lib32stdc++6
$ apt install lib32z1

开机后提示：检测到系统程序出现问题的解决方法

$ vi /etc/default/apport
改为enabled=0