error: EC2 machine 'm' does not have a private IPv4 address (yet)

[coretemp]

I am looking in the AWS Console, and I see after a refresh that machine m has a private IPv4 address. However, nixops ssh m reports:

error: EC2 machine 'm' does not have a private IPv4 address (yet)

This is a bug or a design bug. It could use the AWS EC2 API to locate the IPv4 address for example.

[coretemp]

There is another inconsistency here, which is that
ssh -i a.pem root@<ip as rapported by AWS Console> works.

IMHO, nixops ssh m should work in at least the cases that ssh works as displayed by the Amazon Connect button.

All this happened when I was downgrading (the instance type) of two exactly the same machines of which only one came up fine (let's call that machine n).

[coretemp]

nixops check returns:

m............> warning: IP address has changed, you may need to run ‘nixops deploy’, which is not useful, because nixops deploy has no effect at all.