[SOLVED] shell_exec

pradeepspa · 08-31-2016, 12:48 PM

Folks,

I am experiencing an issue where there is a php script which ssh into remote host and get the output of few commands. It was working fine but all of sudden with no changes, it stopped working.
When I try ssh manually using the same key the script use, it works absolutely fine. However this issue happens only through php script.

Below is the command in the script,

Quote:

shell_exec("echo \<FONT FACE="courier"\>;/usr/bin/ssh -i //var/www/html/lte/id_rsa root@xxx

I am seeing the http error in log file whenever i load that php script.

Quote:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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 the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
7f:6b:72:2d:49:38:35:9d:51:a1:af:0f:9c:b3:8c:6f.
Please contact your system administrator.
Add correct host key in /var/www/.ssh/known_hosts to get rid of this message.
Offending key in /var/www/.ssh/known_hosts:106
RSA host key for xxxxx has changed and you have requested strict checking.
Host key verification failed.

I know the error is so familiar but I have tried all possible ways mentioned in internet. The error which says "Offending key in /var/www/.ssh/known_hosts:106" . I dont find line 106 on known_host file on both server and client.

I have tried ssh-keygen -R <hostname> on both server and client but no luck.

Could someone give me hand please?

j-ray · 09-01-2016, 02:35 AM

If you know that the server is the one you trust in and has changed remove the line where the server's key is stored in /var/www/.ssh/known_hosts on the client. The server name or its IP should be in a readable format.
Hope this helps
J

pradeepspa · 09-01-2016, 06:12 AM

I have alredy tried that. One think i dont understand is , if you say install server's key in /var/www/.ssh/known_hosts on client side, you mean private key of server?

jpollard · 09-01-2016, 06:28 AM

It is the public key of the host identified in the "known host" file on the system running the PHP script.

One of the things that can do this is upgrades to the remote system, when/if that upgrade replaces the sshd keys. Sshd will generate keys when it starts, thus it will get a new public/private key. Any system that uses the OLD key (as stored in their "known host" file will get a "WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED" when they attempt to make a connection.

pradeepspa · 09-01-2016, 06:32 AM

Thanks. I have manually entered the proper public key which fixed the issue. Thanks a lot folks.