Multiple NICs on the same IPv4 network issue in Fix Common Problems, but not set up as such

[asopala]

Hey all,

 

I'm having this particular issue brought up by Fix Common Problems, and I'm not sure what to do to change it.  It's saying that both the primary NIC and the 10gbps NIC I have installed are on the same IPv4 network, but I have one set to 192.168.0.xxx while the other is on 192.168.75.xxx.  It's telling me they are both on the 192.168.0.xxx network, and I'm not sure why. 

 

I've attached the syslog, let me know if there's anything else I need to attach.

 

 

alexnas-diagnostics-20210422-2305.zip

[ljm42]

eth2 has an IP of 192.168.75.3 and a netmask of 255.255.0.0. That means it participates on the 192.168.x.x network and thus conflicts with eth0 on 192.168.0.x

 

You should change the netmask for eth2 to 255.255.255.0

[asopala]

I don't seem to have the option to change the network mask.  Is it somewhere else?

[ljm42]

Oh the webgui displays it in CIDR format... on eth2, change /16 to /24.

 

I would also check the rest of the devices on that network and make sure they use 255.255.255.0 (or CIDR /24) too

[asopala]

That did it.  Thanks!  BTW, what is the /16 and /24 representing?  I was always confused by that.

[itimpi]

17 minutes ago, asopala said:

That did it.  Thanks!  BTW, what is the /16 and /24 representing?  I was always confused by that.

The number of bits in the mask

[ljm42]

Here is a table that shows how CIDR notation converts to Dotted Decimal Netmask:

   https://kb.wisc.edu/ns/page.php?id=3493