{"id":103,"date":"2022-10-14T13:16:02","date_gmt":"2022-10-14T11:16:02","guid":{"rendered":"https:\/\/www.funkgui.it\/?p=103"},"modified":"2022-10-14T13:16:02","modified_gmt":"2022-10-14T11:16:02","slug":"script-failover-linux","status":"publish","type":"post","link":"https:\/\/www.funkgui.it\/index.php\/script-failover-linux\/","title":{"rendered":"Script failover linux"},"content":{"rendered":"\n

Ecco uno script da utilizzare in caso di doppia connessione WAN su un server linux in modo da poter switchare da una all’altra in caso di down della linea.<\/p>\n\n\n\n

\u00e8 pensata per essere impostato come cron ad esempio con una configurazione del genere<\/p>\n\n\n\n

*\/1 * * * * \u00a0\u00a0\u00a0\u00a0root \u00a0\u00a0\u00a0\/opt\/internetGatewayFailover<\/code><\/p>\n\n\n\n

Ecco lo script:<\/p>\n\n\n\n

#!\/bin\/bash

CHECK_IP=${CHECK_IP:-8.8.4.4}
PRIMARY_IF=${PRIMARY_IF:-eth0}
PRIMARY_GW=${PRIMARY_GW:-172.16.0.1}
BACKUP_IF=${BACKUP_IF:-eth1}
BACKUP_GW=${BACKUP_GW:-192.168.3.20}

# Compare arg with current default gateway interface for route to healthcheck IP
getGwInterface() {
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 1 interfaccia
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0[[ \"$1\" = \"$(ip route get \"$CHECK_IP\" | sed -rn 's\/^.*dev ([^ ]*).*$\/\\1\/p')\" ]]
}
checkConnectivity() {
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 1 interfaccia \u00a0
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 2 gateway
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0ip route add \"$CHECK_IP\" via $2 dev $1
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0PING_res=`ping -I $1 -c1 \"$CHECK_IP\"|grep 'packet loss'|cut -d ' ' -f4`
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0#echo $PING_res
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0ip route del \"$CHECK_IP\" via $2 dev $1
}
switchGw(){
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 1 attuale gateway da rimuovere
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 2 attuale interfaccia gateway da rimuovere
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 3 nuovo gateway
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0# parametro 4 interfaccia nuovo gateway
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0ip route del default via \"$1\" dev \"$2\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0ip route add default via \"$3\" dev \"$4\"
}


if ping -c1 \"$CHECK_IP\" &>\/dev\/null
then
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0if getGwInterface \"$PRIMARY_IF\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0then
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Connessione attiva su gateway primario\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0exit
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0else
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Connessione attiva su gateway backup\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Switch se possibile su connessione primaria\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0checkConnectivity \"$PRIMARY_IF\" \"$PRIMARY_GW\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0if [[ \"$PING_res\" = \"1\" ]] \u00a0
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0then
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Switch possibile su primario\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0switchGw \"$BACKUP_GW\" \"$BACKUP_IF\" \"$PRIMARY_GW\" \"$PRIMARY_IF\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0else
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Switch non possibile.... rimango su backup ed esco\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0exit
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0fi
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0fi
else
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Connessione NON attiva\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0if getGwInterface \"$PRIMARY_IF\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0then
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Switch comunque su backup\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0switchGw \"$PRIMARY_GW\" \"$PRIMARY_IF\" \"$BACKUP_GW\" \"$BACKUP_IF\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0exit
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0else
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0echo \"Switch comunque su primario\" \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0switchGw \"$BACKUP_GW\" \"$BACKUP_IF\" \"$PRIMARY_GW\" \"$PRIMARY_IF\"
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0fi
fi


exit
<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"

Ecco uno script da utilizzare in caso di doppia connessione WAN su un server linux in modo da poter switchare da una all’altra in caso di down della linea. \u00e8 pensata per essere impostato come cron ad esempio con una configurazione del genere *\/1 * * * * \u00a0\u00a0\u00a0\u00a0root \u00a0\u00a0\u00a0\/opt\/internetGatewayFailover Ecco lo script: #!\/bin\/bash CHECK_IP=${CHECK_IP:-8.8.4.4}PRIMARY_IF=${PRIMARY_IF:-eth0}PRIMARY_GW=${PRIMARY_GW:-172.16.0.1}BACKUP_IF=${BACKUP_IF:-eth1}BACKUP_GW=${BACKUP_GW:-192.168.3.20} […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":true,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-103","post","type-post","status-publish","format-standard","hentry","category-linux"],"_links":{"self":[{"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/posts\/103","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/comments?post=103"}],"version-history":[{"count":1,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/posts\/103\/revisions"}],"predecessor-version":[{"id":105,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/posts\/103\/revisions\/105"}],"wp:attachment":[{"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/media?parent=103"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/categories?post=103"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.funkgui.it\/index.php\/wp-json\/wp\/v2\/tags?post=103"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}