Hi, all
I migrate a vm from source host to the destination host. 
I am sure every part is ok for migration.

1   Create the  image in the destination and change the user and group.
2   Open TCP socket in the destination host. 

and I migrate in the source host command line.   
$ virsh migrate --live --copy-storage-all vmubuntu  qemu+ssh://destinationHost/system --verbose
But I get the  error
"error: operation failed : failed to retrieve chardev info inqemu with 'info chardev'" 
In the destination I find in the vmubuntu.log  
The error is 
"Migration failed. Exit code tcp:0.0.0.0:49170(-98),exiting."

What can I do to solve it ? 
I do not understand how the error comes.
Anyone can help me ?
Thanks in advance.