b1873: Reverse proxy healthcheck simplified.

configuration/environments_scripts/reverse_proxy/files/var/www/cgi-bin/reverseProxyHealthcheck.sh

@@ -1,7 +1,6 @@
 #!/bin/bash
 
-# Purpose: This script identifies whether the instance the script runs on is in the same AZ as the archive.
-# The user it is installed on must have aws credentials that don't need mfa. Install to  /usr/share/httpd/.aws.
+# Purpose: This script is the internal server status.
 
 outputMessage() {
     # parameter 1: the message to display on the site
@@ -15,58 +14,12 @@ status() {
     echo "Status: $1"
 }
 
-convert_ip_to_num() {
-    # $1: Ip4 address in 4 octets form, separated by 3 dots.
-    IFS=. read -r a b c d <<< "$1"
-    echo "$(( ( $a << 24 ) + ( $b << 16 ) +  ($c << 8 ) + ($d) ))"
-}
 SELF_IP=$( ec2-metadata --local-ipv4 | grep   -o "[0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+\>")
 curl --silent --location --fail "http://${SELF_IP}/internal-server-status" >/dev/null
-if [[ "$?" -ne 0 ]]; then
-    status "500 Reverse proxy itself is unhealthy"
-    outputMessage "Reverse proxy is unhealthy"
-    exit 0
-fi
-# The names of the variables in the macros file.
-ARCHIVE_IP_NAME="ARCHIVE_IP"
-ARCHIVE_FAILOVER_IP_NAME="ARCHIVE_FAILOVER_IP"
-PRODUCTION_IP_NAME="PRODUCTION_ARCHIVE"
-MACROS_PATH="/etc/httpd/conf.d/000-macros.conf"
-# The regex to extract the ip from a line ending in an ip.
-IP_REGEX="[0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+$"
-# Extracts which IP is in production.
-PRODUCTION_IP=$(sed -n -e  "s/^Define ${PRODUCTION_IP_NAME}\> \(.*\)$/\1/p" ${MACROS_PATH})
-SUBNET_MASK_SIZE_VAR_LOCATION="/var/cache/subnetMaskSize"
-if [[ ! -e "$SUBNET_MASK_SIZE_VAR_LOCATION" ]]; then
-    # Get subnet mask size
-    MY_AZ=$( ec2-metadata --availability-zone | grep -o "[a-zA-Z]\+-[a-zA-Z]\+-[0-9a-z]\+\>")
-    aws ec2 describe-subnets | jq -r '.Subnets[] | select( .AvailabilityZone =="'"$MY_AZ"'") | .CidrBlock | split("/") | .[1]' > $SUBNET_MASK_SIZE_VAR_LOCATION
-fi
-if [[ "$PRODUCTION_IP" == "\${${ARCHIVE_IP_NAME}}" ]]
-then
-    # Check if main archive is in the same az by comparing the network portion of the archive and this instance's IP, with the same bitmask.
-    MY_IP=$( ec2-metadata --local-ipv4 | grep   -o "[0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+\>")
-    MY_IP_VALUE="$(convert_ip_to_num "$MY_IP")"
-    MY_AZ_MASK_SIZE=$(cat $SUBNET_MASK_SIZE_VAR_LOCATION) 
-    # convert the value after the CIDR slash into a bitmask
-    BITMASK_VALUE=0
-    for i in $(seq $((31 - $MY_AZ_MASK_SIZE + 1)) 31); do
-        BITMASK_VALUE=$(($BITMASK_VALUE | (1 << i ) ))
-    done
-    MY_SUBNET_VALUE=$(($BITMASK_VALUE & $MY_IP_VALUE))
-    # Extract the actual IP of the archive
-    ARCHIVE_IP=$(grep -m 1 "^Define ${ARCHIVE_IP_NAME}\> .*"  ${MACROS_PATH} | grep -o "${IP_REGEX}")
-    ARCHIVE_IP_VALUE=$(convert_ip_to_num "$ARCHIVE_IP")
-    ARCHIVE_SUBNET_VALUE=$(($BITMASK_VALUE & $ARCHIVE_IP_VALUE ))  #A Aply the mask to the archive IP value.
-    if [[ "$ARCHIVE_SUBNET_VALUE"  -eq  "$MY_SUBNET_VALUE" ]]; then 
-        status "200"
-        outputMessage "Healthy: in the same az as the archive"
-    else 
-        status "503 Not in the same az"
-        outputMessage "Unhealthy: Not in the same az as the archive"
-    fi
-else
-    # We don't check if failover archive is in the same az
+if [[ "$?" -eq 0 ]]; then
     status "200"
     outputMessage "failover at play: force healthy"
-fi
+else
+    status "500 Reverse proxy itself is unhealthy"
+    outputMessage "Reverse proxy is unhealthy"
+fi