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We have a system image which uses a default password for root. This should be changed, though I have a feeling not all users do this.

I know I can test login with pamtester:

# pamtester system-auth root authenticate

It asks for the password on the command line. I want to automate this. Can this be done?

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up vote 0 down vote accepted

Yes, by using the Expect scripting language.

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Check for the hash in the /etc/shadow file. You already have the hash, since it's part of your image. Just make sure the root password hash is different.

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A here-document does the trick as well:

testparm ... << eof
`echo $password`
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It is not really clear to me, how does it work. I suggest to elaborate your answer. – peterh Jun 19 '15 at 15:43

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