Home / server / Questions / 72708
Accepted
aaron
Asked: 2009-10-09 13:14:42 +0800 CST

execute su -c over ssh

  • 772

I am trying to check the BIOS version of a server over SSH, a command that requires root privileges:

ssh remote-server su -c dmidecode

but this of course fails with the error:

standard in must be a tty

How do I make this work? I cannot use sudo, and when I try to log in as root@remote-server, it won't accept the password I use for the 'su' command. I am using RedHat Enterprise Linux 4.

ssh

2 Answers

  1. Best Answer

    Use -t to force ssh to allocate a tty:

    ssh -t -t remote-user su -c dmidecode

    You might also consider allowing root to ssh directly. If you're using public key authentication, this may be more secure as you won't be passing a password around. If you decide to do this, consider blocking root logins from anywhere except your trusted IP addresses by putting the following in /etc/security/access.conf:

    + : root : 10.20.30.40
- : root : ALL EXCEPT LOCAL

    and make sure UsePAM isn't disabled in sshd_config

    • 14

  2. Can't you just log in to the remote server as a standard user and then use sudo?

    You could also try quoting the command to be executed by ssh, as in

    ssh remote-server 'su -c dmidecode'

    or

    ssh remote-server "su -c dmidecode"
    • 0