Originally published October 26, 2016 @ 11:50 pm
This is a simple one: get a list of MX records for the given domains and output into CSV file. Really, the only interesting part of this is the use of array to temporarily store output of the dig command. The array is later used to prepend the correct number of column headers to the CSV file. This can be particularly useful if the output is used to generate a database table.
#!/bin/bash
infile="/tmp/domainlist.txt"
outfile="/tmp/domainlist_mx.csv"
IFS=$'\n'; a=($(for d in `grep -v ^# "${infile}" | grep .`; do mx="$(timeout 10 dig ${d} MX 2>/dev/null | \
grep "^${d}.*MX" | awk '{print $NF}' | sort -u | sed 's/\.$//g')"; if [ ! -z "${mx}" ]; then echo ${d} ${mx} | \
sed 's/ /,/g'; else echo ${d}; fi; done)); unset IFS
printf '%s\n' ${a[@]} | printf '%s\n' ${a[@]} | (echo "DOMAIN,$(for i in $(seq 1 $(printf '%s\n' ${a[@]} | \
awk -F, '{if (NF > max) {max = NF}} END{print max}')); do echo -n "MX_RECORD_${i},"; done | sed 's/,$//g')" && cat) | \
tee "${outfile}"
Experienced Unix/Linux System Administrator with 20-year background in Systems Analysis, Problem Resolution and Engineering Application Support in a large distributed Unix and Windows server environment. Strong problem determination skills. Good knowledge of networking, remote diagnostic techniques, firewalls and network security. Extensive experience with engineering application and database servers, high-availability systems, high-performance computing clusters, and process automation.
