How to control traffic, is there a usb0 interface besides eth0?

Question

linux

All devices at home are connected through one common router (which in turn connects via pppoe to the servers of the local provider:

[email protected]:~$ traceroute toster.ru
traceroute to toster.ru (178.248.236.52), 30 hops max, 60 byte packets
 1  router.asus.com (192.168.1.1)  0.579 ms  1.344 ms  1.147 ms
 2  10.91.255.126 (10.91.255.126)  5.658 ms  6.022 ms  6.321 ms
 3  lag-6-435.bbr01.nn.ertelecom.ru (91.144.153.98)  13.886 ms  14.341 ms  14.484 ms
 4  * * *
 5  mskn08.transtelecom.net (188.43.11.122)  22.468 ms  22.531 ms  22.759 ms
 6  * * *
 7  HLL-gw.transtelecom.net (217.150.47.233)  19.652 ms  19.334 ms  19.539 ms
 8  * * *
 9  * * *
10  * * *
11  * * *
12  * * *
13  * * *
14  * * *
15  * * *
16  * * *
17  * * *
18  * * *
19  * * *
20  * * *
21  * * *
22  * * *
23  * * *
24  * * *
25  * * *
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *

In addition to Ethernet / RJ45, an Android phone is connected to the computer (it is used as a wifi / usb modem):

[email protected]:~$ ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:1a:4d:91:2b:c0  
          inet addr:192.168.1.153  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: ::5f4e:15dd:1c1c:7a20:fc5a:5b79/64 Scope:Global
          inet6 addr: fe80::21a:4dff:fe91:2bc0/64 Scope:Link
          inet6 addr: ::5f4e:15dd:21a:4dff:fe91:2bc0/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:22057 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10689 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:28831308 (28.8 MB)  TX bytes:1286317 (1.2 MB)

[email protected]:~$ ifconfig usb0
usb0      Link encap:Ethernet  HWaddr 0e:d2:6d:8b:88:74  
          inet addr:192.168.42.53  Bcast:192.168.42.255  Mask:255.255.255.0
          inet6 addr: fe80::cd2:6dff:fe8b:8874/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:29 errors:0 dropped:0 overruns:0 frame:0
          TX packets:78 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2885 (2.8 KB)  TX bytes:12885 (12.8 KB)

Having done a path tracing (you can see that all traffic goes through eth0):

[email protected]:~$ traceroute 192.168.1.1
traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
 1  router.asus.com (192.168.1.1)  0.517 ms  0.470 ms  1.027 ms
[email protected]:~$ ip route
default via 192.168.1.1 dev eth0  proto static 
192.168.1.0/24 dev eth0  proto kernel  scope link  src 192.168.1.153  metric 1 
192.168.42.0/24 dev usb0  proto kernel  scope link  src 192.168.42.53  metric 1 
[email protected]:~$ traceroute 192.168.42.1
traceroute to 192.168.42.1 (192.168.42.1), 30 hops max, 60 byte packets
 1  ii (192.168.42.53)  2998.310 ms !H  2998.231 ms !H  2998.217 ms !H

How to make traffic pass through the usb0 interface? (while eth0 must remain active)

Answer 1

How to make traffic pass through the usb0 interface? (while eth0 must remain active)

In the routing table, use usb0 instead of eth0 as the default gateway.
Enter something like:
ip route add default via 192.168.42.1