Add checks with helpful debug information

emailwiz.sh

@@ -23,6 +23,12 @@ subdom=${MAIL_SUBDOM:-mail}
 maildomain="$subdom.$domain"
 certdir="/etc/letsencrypt/live/$maildomain"
 
+# Preliminary record checks
+ipv4=$(host "$domain" | grep -m1 -Eo '([0-9]+\.){3}[0-9]+')
+[ -z "$ipv4" ] && echo "\033[0;31mPlease point your domain ("$domain") to your server's ipv4 address."
+ipv6=$(host "$domain" | grep "IPv6" | awk '{print $NF}')
+[ -z "$ipv6" ] && echo "\033[0;31mPlease point your domain ("$domain") to your server's ipv6 address."
+
 # Open required mail ports, and 80, for Certbot.
 for port in 80 993 465 25 587; do
 	ufw allow "$port" 2>/dev/null
@@ -347,14 +353,10 @@ for x in opendkim dovecot postfix fail2ban; do
 	systemctl enable "$x"
 done
 
-# Generate spf mechanisms
-mailip4=$(host "$domain" | grep -m1 -Eo '([0-9]+\.){3}[0-9]+')
-mailip6=$(host "$domain" | grep "IPv6" | awk '{print $NF}')
-
 pval="$(tr -d '\n' <"/etc/postfix/dkim/$domain/$subdom.txt" | sed "s/k=rsa.* \"p=/k=rsa; p=/;s/\"\s*\"//;s/\"\s*).*//" | grep -o 'p=.*')"
 dkimentry="$subdom._domainkey.$domain	TXT	v=DKIM1; k=rsa; $pval"
 dmarcentry="_dmarc.$domain	TXT	v=DMARC1; p=reject; rua=mailto:dmarc@$domain; fo=1"
-spfentry="$domain	TXT	v=spf1 mx a:$maildomain ip4:$mailip4 ip6:$mailip6 -all"
+spfentry="$domain	TXT	v=spf1 mx a:$maildomain ip4:$ipv4 ip6:$ipv6 -all"
 mxentry="$domain	MX	10	$maildomain	300"
 
 useradd -m -G mail dmarc