[Hyper-V][Azure]ssh session will timeout for a short while for FreeBSD on Azure

[Hongjiang Zhang]

If we install cloud-init on a FreeBSD VHD which does not install waagent previously, and upload this VHD to Azure. It works fine for SSH connection. But after a short while (~5 seconds), the SSH session is broken.

The reason is cloud-init does not set "ClientAliveInterval" in /etc/ssh/sshd_config.

[Scott Moser (smoser)]

For what its worth, this affects Ubuntu too.
I never understood why this change is needed.
Why is the platform so agressive on dropping network connections?

[Hongjiang Zhang (redriver)]

>For what its worth, this affects Ubuntu too.
 >I never understood why this change is needed.
 >Why is the platform so agressive on dropping network connections?
 >

The ssh session will not break in local VM even after a long time idle, but on Azure, the session is broken after a short time of idling.
Currently, I did not find a simple solution to handle this except for change the sshd_config file (waagent has done it)
This is in fact an improvement of user experience. So, it is not quite urgent. Let me think about it further.

Thanks
Hongjiang Zhang
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 >Title:
 > [Hyper-V][Azure]ssh session will timeout for a short while for FreeBSD
 > on Azure
 >
 >Status in cloud-init:
 > Confirmed
 >
 >Bug description:
 > If we install cloud-init on a FreeBSD VHD which does not install
 > waagent previously, and upload this VHD to Azure. It works fine for
 > SSH connection. But after a short while (~5 seconds), the SSH session
 > is broken.
 >
 > The reason is cloud-init does not set "ClientAliveInterval" in
 > /etc/ssh/sshd_config.
 >
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[James Falcon (falcojr)]

Tracked in Github Issues as https://github.com/canonical/cloud-init/issues/2927