I'm setting up an embedded Linux system and accessing it via SSH for development purposes. I've set up a static IP address and a Dropbear SSH server, and both appear to be working for the most part.
I can access the device with its IPv6 address, but the handshake times out when I use its IPv4 address. I've tried changing said address in case it was taken, but it didn't change anything. I've also tried adding firewall rules to ensure that the SSH client wouldn't be blocked.
I've looked around for information on what could cause this, but the closest thing I could find was a question asking about why Dropbear worked on IPv4 but not IPv6. I have the opposite problem. I would simply use IPv6 and bypass the issue, but the system will eventually need to be accessed via a Node.js server over HTTP. I don't want it to require an IPv6 address in the URL.
I suspect that the problem might have something to do with the address scopes, as the IPv6 is listed as
scope link while the IPv4 is listed as
scope global eth0. (I'm connecting the board directly to the computer with an Ethernet cable.) If this is in fact the problem, is there a way to configure address scopes? I couldn't find anything on that particular topic.
The relevant information is below:
~# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue 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: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0a:35:00:eb:e9 brd ff:ff:ff:ff:ff:ff inet 192.168.0.130/24 brd 192.168.0.255 scope global eth0 valid_lft forever preferred_lft forever inet6 fe80::20a:35ff:fe00:ebe9/64 scope link valid_lft forever preferred_lft forever ~# ip route default via 192.168.0.1 dev eth0 192.168.0.0/24 dev eth0 src 192.168.0.130 ~# ip link 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0a:35:00:eb:e9 brd ff:ff:ff:ff:ff:ff ~# ip tunnel ~# netstat -a Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 *:ftp *:* LISTEN tcp 0 0 *:ssh *:* LISTEN tcp 0 0 *:telnet *:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN getnameinfo failed getnameinfo failed tcp6 0 0 [UNKNOWN]:ssh [UNKNOWN]:1755 ESTABLISHED Active UNIX domain sockets (servers and established) Proto RefCnt Flags Type State I-Node Path