[SOLVED] 14.2 Multilib Can't Even Ping Router but Current Works Fine. Why?

Greetings and thank you in advance for any suggestions

Recently my Main motherboard failed and I'm trying to deploy an older PC as a substitute until I can replace/repair my Main. Slackware Current (upon which this is being typed now) and other OpSys work fine but my Main is 14.2 MultiLib and though DHCPD gets the correct IP from my router, and "ifconfig" and "route" shows nearly identical parameters, in 14.2 I can ping myself, so Loopback is working, but I can't even ping my Gateway.

I've spent more than a day trying to determine what is wrong or missing but without being at least able to get to my router, I'm stuck.

What tests or changes can I make that might help me gather the information I need to fix this?

FWIW here's some data from Current vs/ 14.2.

CURRENT

bash-4.4# ifconfig eth0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.0.0.3  netmask 255.255.255.0  broadcast 10.0.0.255
        inet6 fe80::227:eff:fe12:5fa4  prefixlen 64  scopeid 0x20<link>
        ether 00:27:0e:12:5f:a4  txqueuelen 1000  (Ethernet)
        RX packets 16582  bytes 15916145 (15.1 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 13790  bytes 1867866 (1.7 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 20  memory 0xdb100000-db120000  

bash-4.4# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.0.1        0.0.0.0         UG    202    0        0 eth0
10.0.0.0        0.0.0.0         255.255.255.0   U     202    0        0 eth0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo

bash-4.4# ping 10.0.0.3
PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data.
64 bytes from 10.0.0.3: icmp_seq=1 ttl=64 time=0.063 ms
64 bytes from 10.0.0.3: icmp_seq=2 ttl=64 time=0.041 ms
 64 bytes from 10.0.0.3: icmp_seq=3 ttl=64 time=0.038 ms
64 bytes from 10.0.0.3: icmp_seq=4 ttl=64 time=0.040 ms
^C
--- 10.0.0.3 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 97ms
rtt min/avg/max/mdev = 0.038/0.045/0.063/0.012 ms
bash-4.4# ping 10.0.0.1
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=0.651 ms
64 bytes from 10.0.0.1: icmp_seq=2 ttl=64 time=0.285 ms
64 bytes from 10.0.0.1: icmp_seq=3 ttl=64 time=0.295 ms
64 bytes from 10.0.0.1: icmp_seq=4 ttl=64 time=0.289 ms
^C
--- 10.0.0.1 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 66ms
rtt min/avg/max/mdev = 0.285/0.380/0.651/0.156 ms

14.2 Multilib

 bash-4.3# ifconfig eth1
eth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.0.0.3  netmask 255.255.255.0  broadcast 10.0.0.255
        inet6 fe80::227:eff:fe12:5fa4  prefixlen 64  scopeid 0x20<link>
        ether 00:27:0e:12:5f:a4  txqueuelen 1000  (Ethernet)
        RX packets 5  bytes 1067 (1.0 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 16  bytes 1913 (1.8 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 20  memory 0xdb100000-db120000  

bash-4.3# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.0.1        0.0.0.0         UG    202    0        0 eth1
10.0.0.0        0.0.0.0         255.255.255.0   U     202    0        0 eth1
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo

bash-4.3# ping 10.0.0.3
PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data.
64 bytes from 10.0.0.3: icmp_seq=1 ttl=64 time=0.043 ms
64 bytes from 10.0.0.3: icmp_seq=2 ttl=64 time=0.038 ms
64 bytes from 10.0.0.3: icmp_seq=3 ttl=64 time=0.043 ms
^C (after ~2 seconds)
--- 10.0.0.3 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2053ms
rtt min/avg/max/mdev = 0.038/0.041/0.043/0.005 ms

bash-4.3# ping 10.0.0.1
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
^C (after 70 seconds)
--- 10.0.0.1 ping statistics ---
0 packets transmitted, 0 received

TLDR - Given this is demonstrably not a hardware issue, what tests or changes can I make that might help me gather the information I need to at least communicate effectively with my router beyond simply assigning an IP lease? Is it 10.0.0.0 flags? and if so, how did that happen and how do I fix it?

--- 10.0.0.1 ping statistics ---
0 packets transmitted, 0 received

Looks like no packet was sent, which may explain why your gateway never answered.

What does

# ip neigh

tell you?

Originally Posted by Alien Bob --- 10.0.0.1 ping statistics --- 0 packets transmitted, 0 received Looks like no packet was sent, which may explain why your gateway never answered.

Naturally I did realize none was sent but I have no idea how that can occur. After all I repeatedly try ping and I do get the loopback output when I ping the PCs addy as I displayed above. So doesn't that mean it sometimes sends and just doesn't receive? I'm suspecting of course some obstacle at communicating with the router beyond just the simple IP lease.

One factor to also consider is that I literally dropped the drives from my Main into this substitute and while the brand and model of the onboard nics is different, they both obviously work in some settings (different opsys/version) 14.2 worked before with the previous nic but doesn't with the "new",different nic even though it does with with current and other OpSys. I have no idea why it didn't just work in 14.2 without any alterations as it does in Current?

How do I address the issue that it didn't send to it's own Gateway?.. and as an aside why would it require any changes given the network setup worked before?

Originally Posted by luvr What does # ip neigh tell you?

Thanks luvr (geez that sounds intimate )

Sorry to take so long but I had to install iproute2 since I don't upgrade my full installs unless I'm forced to, excepting security patches. I also had to familiarize myself with the "ip" command as it's new to me. I've known about it but always relied on ifconfig.

In any case I had to familiarize myself with "ip" discovering I had to initiate some sort of contact first before it would register which, of course, it did on this Current <reachable>, but did not give any output for "neighbor" on 14.2. It did answer to "ip route" and "ip address" so at least I know it functions. On top of that I'm glad to discover the tool, thanks to your inquiry, as it has some of the power I'm seeking to even see let alone troubleshoot network data.

I had tried to get "ipscan" from Slackbuilds.org but apparently a brief look-see says it needs jdk-8 and Oracle's oldest listed is now v12 so I stopped until I have more to go on.

Anyway, TLDR, no output at all from "ip neighbor" (not sure it even accepted the abbreviation in the older version available for 14.2)
So now what?

Originally Posted by enorbet One factor to also consider is that I literally dropped the drives from my Main into this substitute

Delete /etc/udev/rules.d/70-persistent-net.rules

Thank you GazL. That actually worked. Why did this even ever occur?

Because of the old entry in that file, eth0 was still looking for your old hardware, which wasn't there. Your new interface was likely assigned to eth1 instead. Deleting the file lets the system regenerate it and assign 'eth0' to the new hardware.

Originally Posted by GazL Because of the old entry in that file, eth0 was still looking for your old hardware, which wasn't there. Your new interface was likely assigned to eth1 instead. Deleting the file lets the system regenerate it and assign 'eth0' to the new hardware.

Thanks, Gazl. Sounds like a good reason for hard assignments or better automation. Seems to me that might be fixable with an "if exists".

Originally Posted by GazL Because of the old entry in that file, eth0 was still looking for your old hardware, which wasn't there. Your new interface was likely assigned to eth1 instead. Deleting the file lets the system regenerate it and assign 'eth0' to the new hardware.

Been looking for this answer since 14.2 came out. Thank you.