How to check root certificate expiration date with bash on Linux

How do we check the expiration date of an SSL certificate including root certificate on Linux with bash shell?

You could do something like this:

openssl s_client -connect THESITE:443 </dev/null 2>/dev/null \
    |awk '/BEGIN CERT/,/END CERT/' |tee /tmp/asdf

to extract the certificate itself…

then, to inspect the certificate,

openssl x509 -text -in /tmp/asdf |grep -A2 Validity
            Not Before: Feb  5 14:32:26 2020 GMT
            Not After : Apr  5 21:02:01 2022 GMT…

Hope this helps.

1 Like

@vocatan thanks it worked :slight_smile: since we store it in file I can grep them in shell variables too.


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