How to log ssh debug info?

Question

I need to write the output of ssh debug info into the file. This

ssh -v root@172.16.248.xx > result.txt
ssh -v root@172.16.248.xx 2>&1 > result.txt
         


        

Answer 1

 -E log_file
         Append debug logs to log_file instead of standard error.

Answer 2

You have to change the order of the redirections on the command line:

ssh -v root@172.16.248.xx >result.txt 2>&1

or just:

ssh -v root@172.16.248.xx 2>result.txt

Answer 3

Apparently the best way to save this "hidden" debug output to the file is by using logsave:

logsave result.txt ssh -v root@172.16.248.xx