{"id":364,"date":"2016-08-29T10:35:57","date_gmt":"2016-08-29T08:35:57","guid":{"rendered":"http:\/\/itso.dk\/?p=364"},"modified":"2016-08-29T10:36:32","modified_gmt":"2016-08-29T08:36:32","slug":"internet-sharing-ubuntu-16-04-systemd-style","status":"publish","type":"post","link":"https:\/\/blog.itso.dk\/?p=364","title":{"rendered":"Internet Sharing Ubuntu 16.04 – Systemd style"},"content":{"rendered":"

Checklist:<\/h3>\n

Setup interfaces<\/p>\n

Setup dhcp server<\/p>\n

Enable routing<\/p>\n

Setup iptables script<\/p>\n

Setup service to start iptable script on startup.<\/p>\n

 <\/p>\n

Install DHCP server<\/p>\n

apt install isc-dhcp-server<\/pre>\n
 <\/p>\n
\/etc\/dhcp\/dhcpd.conf<\/p>\n
default-lease-time 600;\r\n\r\n max-lease-time 7200;\r\n log-facility local7;\r\n\r\n allow booting;\r\n allow bootp;\r\nsubnet 192.168.52.0 netmask 255.255.255.0 {\r\n range 192.168.52.10 192.168.52.30;\r\n \r\noption broadcast-address 192.168.52.255;\r\n option routers 192.168.52.1;\r\noption domain-name-servers 8.8.8.8;\r\n filename \"pxelinux.0\";\r\n\r\n<\/span> next-Server 192.168.52.1;\r\n }<\/span>\r\n\r\n\r\n<\/pre>\n
Start service and enable at boot<\/p>\n
systemctl start isc-dhcp-server6.service\r\n\r\nsystemctl enable isc-dhcp-server6.service<\/pre>\n
 <\/p>\n
Test by typing<\/p>\n
sudo netstat -uap<\/pre>\n
 <\/p>\n
 <\/p>\n
\/etc\/sysctl.conf<\/p>\n
net.ipv4.ip_forward = 1\r\nnet.ipv4.conf.default.rp_filter = 1<\/pre>\n
<\/div>\n
Restart to take affect.<\/div>\n
sudo systemctl restart systemd-sysctl.service<\/pre>\n
<\/div>\n
<\/div>\n
Creating iptable script<\/h4>\n
\/etc\/myiptable.sh<\/p>\n
#!\/bin\/bash\r\niptables -P INPUT DROP\r\niptables -P\u00a0FORWARD DROP\r\niptables -P\u00a0OUTPUT ACCEPT\r\niptables -I INPUT -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT\r\niptables\u00a0-A INPUT -i wlan0 -j ACCEPT\r\niptables\u00a0-A INPUT -i lo -j ACCEPT\r\niptables\u00a0-A INPUT -i eth0 -p tcp -m tcp --dport 22 -j ACCEPT\r\niptables\u00a0-I FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT\r\niptables\u00a0-A FORWARD -s 192.168.0.0\/24 -i wlan0 -j ACCEPT\r\niptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE<\/pre>\n
<\/div>\n
<\/div>\n
chmod a+x \/etc\/myiptable.sh<\/pre>\n
<\/div>\n
<\/div>\n
Create service to start script on bootup:<\/h4>\n
<\/div>\n
\/etc\/systemd\/system\/mynetwork.service<\/div>\n
[Unit]\r\nDescription= Internet sharing script to enp17s\r\nAfter=network.target\r\n[Service]\r\nType=forking\r\nUser=root\r\nExecStart=\/etc\/myiptable.sh\r\n[Install]\r\nWantedBy=multi-user.target<\/pre>\n
<\/div>\n","protected":false},"excerpt":{"rendered":"
Checklist: Setup interfaces Setup dhcp server Enable routing Setup iptables script Setup service to start iptable script on startup.   Install DHCP server apt install isc-dhcp-server   \/etc\/dhcp\/dhcpd.conf default-lease-time 600; max-lease-time 7200; log-facility local7; allow booting; allow bootp; subnet 192.168.52.0 netmask 255.255.255.0 { range 192.168.52.10 192.168.52.30; option broadcast-address 192.168.52.255; option routers 192.168.52.1; option domain-name-servers 8.8.8.8; …<\/p>\n
Continue reading ‘Internet Sharing Ubuntu 16.04 – Systemd style’ »<\/a><\/p>\n","protected":false},"author":1,"featured_media":293,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-364","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/posts\/364","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=364"}],"version-history":[{"count":11,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/posts\/364\/revisions"}],"predecessor-version":[{"id":408,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/posts\/364\/revisions\/408"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=\/wp\/v2\/media\/293"}],"wp:attachment":[{"href":"https:\/\/blog.itso.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=364"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=364"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.itso.dk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=364"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}