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P_Shepherd_1790's avatar
Icon for Nimbostratus rankNimbostratus
Apr 28, 2015

gtm_add fails on SSH conneciton

BIG-IP running 11.5.1 HF8

When creating a GTM failover pair the process falls down when I run the gtm_add on the secondary unit.

ssh: connect to host port 22: Connection refused ERROR: Can't read remote cert via /usr/bin/ssh.

The Big-IPs have three interfaces; Management, HA and External

I want to setup the GTM pairing between the External interfaces as this is also the interface that will be used for the connection between the datacentres.

I can ping the IP address.

I can SSH to the other two interfaces.

SSH is allowed and all IP addressing is allowed. But when I try to SSH from one to the other on the External interface the connection is refused.

sys sshd {

allow { ALL }

banner disabled

banner-text none

description none

inactivity-timeout 0

include none

log-level info

login enabled


The only hardware between the two devices is the a switch stack.

4 Replies

  • Check the Self-IP configuration for the external interface/VLAN and confirm what the Port Lockdown setting is.


  • Thank you What Lies Beneath.


    Didn't spot that the Port Lockdown was set to allow none.


    Change it to Allow Default and success.


  • if your username is logged to tmos shell (which I guess is appliance mode), you can use username "root" to add LTMs to GTM. Root is presented with bash shell instead of tmos. For redundant LTM systems, you have to add each unit separately to gtm. I have tested this with bigip_add command.