Communication fails on DSA ethernet ports of Banana Pi R1 (Lamobo R1)

I don't get TCP/IP communication running on my Banana PI R1 on the switch ports (i.e., not the separate LAN port which shows up as eth0, which is working). It runs "Debian GNU/Linux 9.8", upgraded from an Armbian image with Debian 8 . This is my /etc/network/interfaces file: allow-hotplug eth0 iface eth0 inet dhcp # Local loopback auto lo iface lo inet loopback # Router ports auto lan1 iface lan1 inet static address 192.168.12.253 netmask 255.255.255.0 network 192.168.12.0 broadcast 192.168.12.255 gateway 192.168.12.253 dns-search greatsoft.local auto lan2 iface lan2 inet static address 192.168.13.253 netmask 255.255.255.0 network 192.168.13.0 broadcast 192.168.13.255 gateway 192.168.13.253 dns-search greatsoft.local auto lan3 iface lan3 inet static address 192.168.14.253 netmask 255.255.255.0 network 192.168.14.0 broadcast 192.168.14.255 gateway 192.168.14.253 dns-search greatsoft.local auto lan4 iface lan4 inet static address 192.168.15.253 netmask 255.255.255.0 network 192.168.15.0 broadcast 192.168.15.255 gateway 192.168.15.253 dns-search greatsoft.local After boot, ifconfig reports these lines (lo0/wlan0 omitted): eth0: flags=4163 mtu 1500 inet 192.168.1.113 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::47:aff:fec1:f535 prefixlen 64 scopeid 0x20 ether 02:47:0a:c1:f5:35 txqueuelen 1000 (Ethernet) RX packets 4581 bytes 816911 (797.7 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 2392 bytes 294521 (287.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 device interrupt 49 lan1: flags=4099 mtu 1500 inet 192.168.12.253 netmask 255.255.255.0 broadcast 192.168.12.255 ether 02:47:0a:c1:f5:35 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lan2: flags=4099 mtu 1500 inet 192.168.13.253 netmask 255.255.255.0 broadcast 192.168.13.255 ether 02:47:0a:c1:f5:35 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lan3: flags=4099 mtu 1500 inet 192.168.14.253 netmask 255.255.255.0 broadcast 192.168.14.255 ether 02:47:0a:c1:f5:35 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lan4: flags=4163 mtu 1500 inet 192.168.15.253 netmask 255.255.255.0 broadcast 192.168.15.255 inet6 fe80::47:aff:fec1:f535 prefixlen 64 scopeid 0x20 ether 02:47:0a:c1:f5:35 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 13 bytes 1070 (1.0 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 The output of "ip -d link show" is (lo0/wlan0 omitted): 2: eth0: mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 3: lan2@eth0: mtu 1500 qdisc noqueue state LOWERLAYERDOWN mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 switchid 00000000 4: lan3@eth0: mtu 1500 qdisc noqueue state LOWERLAYERDOWN mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 switchid 00000000 5: lan4@eth0: mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 switchid 00000000 6: wan@eth0: mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 switchid 00000000 7: lan1@eth0: mtu 1500 qdisc noqueue state LOWERLAYERDOWN mode DEFAULT group default qlen 1000 link/ether 02:47:0a:c1:f5:35 brd ff:ff:ff:ff:ff:ff promiscuity 0 addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 switchid 00000000 For example, if I connect a cable on the lan 4 port and give the connected system an IP address of 192.168.15.250 with netmask 255.255.255.0, ping from Banana PI says: From 192.168.15.253 icmp_seq=1 Destination Host Unreachable arp -n shows Address HWtype HWaddress Flags Mask Iface 192.168.15.250 (incomplete) lan4 It is unclear to me why communication fails. I guess there must be anything missing. Does anybody have a hint for me? https://www.armbian.com/lamobo-r1/