Re: [systemd-devel] networkd: Link local static IP address behind NAT
Thank you Mike and Andrei. Having the dedicated address section with Scope=global solved our issue. We did investigate the Scope option, but did not realize it was both available in the Route and Address section. Thanks again.
Re: [systemd-devel] networkd: Link local static IP address behind NAT
On 18.01.2023 17:12, Thomas Burghout wrote: On 18.01.20233 04:06, Andrei Borzenkov wrote: On 17.01.2023 18:28, Thomas Burghout wrote: inet 169.254.146.171/16 brd 169.254.255.255 scope link eth0 Is it output from the correct system? Because address is different. I do not see how "ping -I 169.254.1.2" can work with this. That is unfortunate, I copied the wrong notes indeed. Apologies. The following output should completely describe the configuration of the system: $ cat /usr/lib/systemd/network/10-lan.network [Match] Name=eth0 [Network] Address=169.254.1.2/16 DNS=169.254.1.1 Gateway=169.254.1.1 $ ip route default via 169.254.1.1 dev eth0 169.254.0.0/16 dev eth0 scope link src 169.254.1.2 $ ip address 1: lo: mtu 65536 qdisc noqueue qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc mq qlen 1000 link/ether e2:26:9e:11:ae:da brd ff:ff:ff:ff:ff:ff inet 169.254.1.2/16 brd 169.254.255.255 scope link eth0 valid_lft forever preferred_lft forever inet6 fe80::e026:9eff:fe11:aeda/64 scope link valid_lft forever preferred_lft forever 3: usb0: mtu 1500 qdisc noop qlen 1000 link/ether b6:c8:ab:ac:44:7f brd ff:ff:ff:ff:ff:ff 4: sit0@NONE: mtu 1480 qdisc noop qlen 1000 link/sit 0.0.0.0 brd 0.0.0.0 $ ip route get 8.8.8.8 8.8.8.8 via 169.254.1.1 dev eth0 $ ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8): 56 data bytes ^C --- 8.8.8.8 ping statistics --- 9 packets transmitted, 0 packets received, 100% packet loss $ ping -I 169.254.1.2 8.8.8.8 PING 8.8.8.8 (8.8.8.8) from 169.254.1.2: 56 data bytes 64 bytes from 8.8.8.8: seq=0 ttl=116 time=12.576 ms 64 bytes from 8.8.8.8: seq=1 ttl=116 time=8.341 ms 64 bytes from 8.8.8.8: seq=2 ttl=116 time=9.124 ms ^C --- 8.8.8.8 ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max = 8.341/10.013/12.576 ms The commands I included for "interactive" were also wrong. The following commands produce a working configuration: ip address flush dev eth0 ip route flush dev eth0 ip address add 169.254.1.2/16 brd + dev eth0 This adds address with global scope. ip route add 169.254.1.1 dev eth0 ip route add default via 169.254.1.1 dev eth0 Most notably, ip route now includes the following line as well: 169.254.1.1 dev eth0 scope link This is red herring. What happens - kernel needs to set source address when you did not specify any. Because route to 8.8.8.8 has global scope and the only available address has link scope, this address is ignored and so no packet can be sent. When you explicitly set source address with -I option kernel simply is using it. If you do ip address add 169.254.1.2/16 brd + dev eth0 scope link you will observe exactly the same behavior. Adding an extra [Route] section with this address does not fix the networkd configuration file. Of course not. But using [Address] Address=169.254.1.2/16 Scope=global does, although I am not sure about possible implications.
Re: [systemd-devel] networkd: Link local static IP address behind NAT
On Wed, Jan 18, 2023 at 9:12 AM Thomas Burghout wrote: > > On 18.01.20233 04:06, Andrei Borzenkov wrote: > > On 17.01.2023 18:28, Thomas Burghout wrote: > > > inet 169.254.146.171/16 brd 169.254.255.255 scope link eth0 > > > > Is it output from the correct system? Because address is different. I do > > not see how "ping -I 169.254.1.2" can work with this. > > That is unfortunate, I copied the wrong notes indeed. Apologies. The > following output should completely describe the configuration of the > system: > > > $ cat /usr/lib/systemd/network/10-lan.network > [Match] > Name=eth0 > > [Network] > Address=169.254.1.2/16 > DNS=169.254.1.1 > Gateway=169.254.1.1 Maybe move Address=169.254.1.2/16 to an Address section with Scope=global. For example: [Address] Address=169.254.1.2/16 Scope=global
[systemd-devel] networkd: Link local static IP address behind NAT
On 18.01.20233 04:06, Andrei Borzenkov wrote: > On 17.01.2023 18:28, Thomas Burghout wrote: > > inet 169.254.146.171/16 brd 169.254.255.255 scope link eth0 > > Is it output from the correct system? Because address is different. I do > not see how "ping -I 169.254.1.2" can work with this. That is unfortunate, I copied the wrong notes indeed. Apologies. The following output should completely describe the configuration of the system: $ cat /usr/lib/systemd/network/10-lan.network [Match] Name=eth0 [Network] Address=169.254.1.2/16 DNS=169.254.1.1 Gateway=169.254.1.1 $ ip route default via 169.254.1.1 dev eth0 169.254.0.0/16 dev eth0 scope link src 169.254.1.2 $ ip address 1: lo: mtu 65536 qdisc noqueue qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc mq qlen 1000 link/ether e2:26:9e:11:ae:da brd ff:ff:ff:ff:ff:ff inet 169.254.1.2/16 brd 169.254.255.255 scope link eth0 valid_lft forever preferred_lft forever inet6 fe80::e026:9eff:fe11:aeda/64 scope link valid_lft forever preferred_lft forever 3: usb0: mtu 1500 qdisc noop qlen 1000 link/ether b6:c8:ab:ac:44:7f brd ff:ff:ff:ff:ff:ff 4: sit0@NONE: mtu 1480 qdisc noop qlen 1000 link/sit 0.0.0.0 brd 0.0.0.0 $ ip route get 8.8.8.8 8.8.8.8 via 169.254.1.1 dev eth0 $ ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8): 56 data bytes ^C --- 8.8.8.8 ping statistics --- 9 packets transmitted, 0 packets received, 100% packet loss $ ping -I 169.254.1.2 8.8.8.8 PING 8.8.8.8 (8.8.8.8) from 169.254.1.2: 56 data bytes 64 bytes from 8.8.8.8: seq=0 ttl=116 time=12.576 ms 64 bytes from 8.8.8.8: seq=1 ttl=116 time=8.341 ms 64 bytes from 8.8.8.8: seq=2 ttl=116 time=9.124 ms ^C --- 8.8.8.8 ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max = 8.341/10.013/12.576 ms The commands I included for "interactive" were also wrong. The following commands produce a working configuration: ip address flush dev eth0 ip route flush dev eth0 ip address add 169.254.1.2/16 brd + dev eth0 ip route add 169.254.1.1 dev eth0 ip route add default via 169.254.1.1 dev eth0 Most notably, ip route now includes the following line as well: 169.254.1.1 dev eth0 scope link Adding an extra [Route] section with this address does not fix the networkd configuration file.
Re: [systemd-devel] networkd: Link local static IP address behind NAT
On 17.01.2023 18:28, Thomas Burghout wrote: Hello, We are trying to configure a device to use a gateway and a static IP address (in the link-local address range). However, the default gateway does not appear to be used. As such, there is no traffic possible to the internet. The device runs systemd 251.4 on a custom Yocto distribution with Linux 5.4.124-altera. The following network is used: [Match] Name=eth0 [Network] Address=169.254.1.2/16 DNS=169.254.1.1 Gateway=169.254.1.1 With this configuration ping 8.8.8.8 does not work. However, if we specify the interface like so: ping -I 169.254.1.2 8.8.8.8 We are able to reach it successfully. We verified that the gateway is indeed reachable. See also the following relevant output: $ ip route default via 169.254.1.1 dev eth0 169.254.0.0/16 dev eth0 scope link src 169.254.146.171 metric 2048 $ ip address 1: lo: mtu 65536 qdisc noqueue qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc mq qlen 1000 link/ether e2:26:9e:11:ae:da brd ff:ff:ff:ff:ff:ff inet 169.254.146.171/16 brd 169.254.255.255 scope link eth0 Is it output from the correct system? Because address is different. I do not see how "ping -I 169.254.1.2" can work with this. valid_lft forever preferred_lft forever 3: usb0: mtu 1500 qdisc noop qlen 1000 link/ether b6:c8:ab:ac:44:7f brd ff:ff:ff:ff:ff:ff 4: sit0@NONE: mtu 1480 qdisc noop qlen 1000 link/sit 0.0.0.0 brd 0.0.0.0 $ ip route get 8.8.8.8 8.8.8.8 via 169.254.1.1 dev eth0 The route seems to be configured correctly. The scope appears to be link, we would expect global as this is consistent with other configurations. The output of ip route get shows no src address. If the interface is configured in an interactive manner we get the expected behavior. The device is able to use the gateway by default. $ ip address flush dev eth0 $ ip route flush dev eth0 $ ip address add 169.254.1.2/16 brd + dev eth0 $ ip route add 169.254.1.1 dev eth0 $ ip route add default via 169.168.1.1 dev eth0 Which produces a route which includes a src address and produces the address with scope global. networkd does not show any warnings or errors in the log. Is there a configuration option we are missing? With kind regards, Thomas Burghout
[systemd-devel] networkd: Link local static IP address behind NAT
Hello, We are trying to configure a device to use a gateway and a static IP address (in the link-local address range). However, the default gateway does not appear to be used. As such, there is no traffic possible to the internet. The device runs systemd 251.4 on a custom Yocto distribution with Linux 5.4.124-altera. The following network is used: [Match] Name=eth0 [Network] Address=169.254.1.2/16 DNS=169.254.1.1 Gateway=169.254.1.1 With this configuration ping 8.8.8.8 does not work. However, if we specify the interface like so: ping -I 169.254.1.2 8.8.8.8 We are able to reach it successfully. We verified that the gateway is indeed reachable. See also the following relevant output: $ ip route default via 169.254.1.1 dev eth0 169.254.0.0/16 dev eth0 scope link src 169.254.146.171 metric 2048 $ ip address 1: lo: mtu 65536 qdisc noqueue qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc mq qlen 1000 link/ether e2:26:9e:11:ae:da brd ff:ff:ff:ff:ff:ff inet 169.254.146.171/16 brd 169.254.255.255 scope link eth0 valid_lft forever preferred_lft forever 3: usb0: mtu 1500 qdisc noop qlen 1000 link/ether b6:c8:ab:ac:44:7f brd ff:ff:ff:ff:ff:ff 4: sit0@NONE: mtu 1480 qdisc noop qlen 1000 link/sit 0.0.0.0 brd 0.0.0.0 $ ip route get 8.8.8.8 8.8.8.8 via 169.254.1.1 dev eth0 The route seems to be configured correctly. The scope appears to be link, we would expect global as this is consistent with other configurations. The output of ip route get shows no src address. If the interface is configured in an interactive manner we get the expected behavior. The device is able to use the gateway by default. $ ip address flush dev eth0 $ ip route flush dev eth0 $ ip address add 169.254.1.2/16 brd + dev eth0 $ ip route add 169.254.1.1 dev eth0 $ ip route add default via 169.168.1.1 dev eth0 Which produces a route which includes a src address and produces the address with scope global. networkd does not show any warnings or errors in the log. Is there a configuration option we are missing? With kind regards, Thomas Burghout
