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I have the following environment:

  1. Oracle Virtual Box installed on PC (Bridged Networking used)
  2. Linux Ubuntu is virtually running on the above-mentioned PC
  3. Few virtual RHELs are installed and running on the same network

Following behavior currently takes place:

  1. SSH connection available between all RHELs and to all RHELs from PC
  2. SSH is available to Ubuntu from PC
  3. SSH is available from Ubuntu to ALL RHELs

My problem is: No SSH connection is available from RHELs to Ubuntu


  • According to nmap scan (and successful login from PC) the 22 port is open and available
  • No rules are defined in IPTABLES

When trying to access from the RHELs to the Ubuntu and using verbose on ssh, only the following appear:

OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008 
debug1: Reading configuration data /etc/ssh/ssh_config 
debug1: Applying options for *     
debug1: Connecting to [] port 22

Any ideas what might cause this behavior?

share|improve this question
Have you tested with ICMP? –  Zoredache Jun 12 '12 at 18:03
@Zoredache You mean pinging? If yes - they yes. Pinging is fine both ways. –  Eugene S Jun 12 '12 at 18:04
Run the sshd on the target system in the foreground -Dddd on an alternative port and attempt to connect with the client to that port with full verbosity (-vvv). –  0xC0000022L Jun 12 '12 at 18:07
Have you ran tcpdump? Is the SSH request getting from the client to the server? –  Zoredache Jun 12 '12 at 18:17
Some kind of DNS checking enabled and no DNS entries for ephemeral VMs? –  rackandboneman Jun 12 '12 at 18:36

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