From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ranch Subject: Re: [AX25] ipv6 incompatible with AX.25 Date: Tue, 25 Jan 2022 10:14:30 -0800 Message-ID: <2394eae7-dada-f43e-40b9-fae929212913@trinnet.net> References: <4B2CD772.1030106@upmc.fr> <4B2D1025.1020106@gmail.com> <4B2E6729.1090102@free.fr> <4B507FAA.8010007@free.fr> <20100115203654.GA3084@del.dom.local> <4DFA6A59.2000709@free.fr> <581f0c8e-f4fb-523d-df6e-7a973b506c34@sorbonne-universite.fr> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <581f0c8e-f4fb-523d-df6e-7a973b506c34@sorbonne-universite.fr> List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: f6bvp@free.fr, linux-hams@vger.kernel.org Cc: List for the LINUX version of FBB , fpac@f6fbb.org, F3KT Hey Bernard, When you saw the lines: -- Jan 25 12:16:31 f6bvp-Ubuntu kernel: [ 6942.400016] IPv6: ADDRCONF(NETDEV_CHANGE): ax0: link becomes ready -- was the AX25 interface not up and usable for classic packet regardless of it's IPv6 state? Generally speaking, I had been been disabling IPv6 for the longest time but I've been leaving it enabled as all of us need to start embracing IPv6. Anyway, on my Ubuntu 20.04 machine, I have IPv6 enabled with AX25 interfaces present though I only have a link local address on my primary Ethernet interface (no IPv6 on ax0). It should be noted I do NOT use AXIPv4 and it wouldn't surprised me if AXIPv6 doesn't work. There are a lot of tools in modern Linuxes that don't even support all aspects of AX25, NETROM, ROSE, etc. in modern tools like "ip", etc. Many of us have to resort to installing legacy tools like ifconfig and route to get the job done. -- $ ip addr 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default 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 fq_codel state UP group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff altname enp0s31f6 inet 192.168.0.25/24 brd 192.168.0.255 scope global dynamic noprefixroute eth0 valid_lft 66471sec preferred_lft 66471sec inet6 fe80::xxxx:xxxx:xxxx:xxxx/64 scope link valid_lft forever preferred_lft forever 3: wlan0: mtu 1500 qdisc noqueue state DOWN group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff altname wlp4s0 4: virbr0: mtu 1500 qdisc noqueue state DOWN group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0 valid_lft forever preferred_lft forever 5: virbr0-nic: mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff 11: ax0: mtu 255 qdisc fq_codel state UNKNOWN group default qlen 10 link/ax25 xx:xx:xx:xx:xx:xx:xx brd a2:a6:a8:40:40:40:00 inet 44.128.0.1/24 scope global ax0 valid_lft forever preferred_lft forever -- > I hope this will help and I have a question. Shall this line be > uncommented in sysctl.conf ? > > # Uncomment the next line to enable packet forwarding for IPv4 > #net.ipv4.ip_forward=1 I question if you really want this on as this should only be enabled if you what your LInux device to be a router (aka.. forwarding packets between one interface and another). This is NOT used if remote stations just want to reach your machine via IP. Fyi, this kernel /proc command alone isn't enough to get routing working. You also need to setup forwarding policies using tools like iptables (legacy) or nftables (newest way). > I actually have the following in my ax25start script : > > ax25start:echo 1 > /proc/sys/net/ipv4/ip_forward Same point as above. --David KI6ZHD