Make an OCSP request with bash via OpenSSL and and obtain the certificate (chain) from the TLS handshake, replay the request with CURL.

ocsp-request-script.sh

#!/bin/bash

if [ "$#" -ne 1 ]; then
    echo
    echo "No hostname given to obtain certificate status"
    echo "\tuse: $0 www.example.com"
    echo
    exit 1
fi

echo
echo Getting certificate for $1 from TLS handshake

openssl s_client -connect $1:443 -servername $1 < /dev/null 2>&1 |  sed -n '/-----BEGIN/,/-----END/p' > certificate.pem

echo
echo Getting intermediates from TLS handshake

openssl s_client -showcerts -connect $1:443 < /dev/null 2>&1 |  sed -n '/-----BEGIN/,/-----END/p' | sed -n '/^-----END CERTIFICATE-----/,$ p' | sed 1d > chain.pem

echo
echo Finding OCSP server in certificate

ocsp=`openssl x509 -noout -ocsp_uri -in certificate.pem`

echo
echo Extracting hostname from OCSP url

## Remove protocol part of url  ##
host=$ocsp
host="${host#http://}"
host="${host#https://}"

## Remove rest of urls ##
host=${host%%/*}

echo
echo "Making OCSP request to $ocsp ($host) saving a copy of the request to ocsp.req and the response to ocsp.resp"

echo
openssl ocsp -noverify -no_nonce -respout ocsp.resp -reqout ocsp.req -issuer chain.pem -cert certificate.pem -text -url $ocsp -header 'Host' $host

echo
echo Making the same OCSP request via CURL
curl -v -o /dev/null --data-binary @ocsp.req -H "Content-Type: application/ocsp-request" --url $ocsp

Hi, Paul!!
Thanks for making this gist available!
It helped me a lot to debug a problem with OCSP inside a kubernetes cluster with Kong!
Using parts of this script I notice that OCSP was failing to get request answer. And that was happening because of Istio that was blocking it.

I needed to make a small correction to the script to it work here.
I change -header 'Host' $host to -header 'Host='$host
Probably due to my openssl version

Well, thanks!