How can I ping through different interfaces (subnets) without using a router device?
I solved the question.
ping -I interface or traceroute -i interface
They aren't the way to check if its working, you don't need to specif the interface because if you do the kernel doesn't use the route table (I guess).
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MaikoID over 1 year
I have a big problem around this issue.
I want to be able to ping and access TFTP through my WIFI interface (wlan0) through my wired interface (eth0)
pc1_eth->LTdhcps2_eth0->LTdhcps2_wlan0->pc2_wlan
and the reverse
pc2_wlan->LTdhcps2_wlan0->LTdhcps2_eth0->pc1_eth
At first I thought that it would be simple because I assumed that I only need to set the gateway of my eth0 with my wlan0's IP.
I was wrong, I was unable to accomplish that.
Let the pain begins..
1) I think the configuration from pc1 and pc2 doesnt metter because it only involves the LTdhcps2 interfaces, am I right ?
Server LTdhcps2
Eth0
cat /etc/network/interfaces # This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback # The primary network interface #allow-hotplug eth0 #iface eth0 inet dhcp auto eth0 iface eth0 inet static address 192.168.2.10 netmask 255.255.255.0
WLAN0
is DHCP configured by network-manager (I couldn't figured out how can I configure it using wpa_supplicant)
After starting the services
service network-manager start service networking start
this the result
[root@LTdhcps2:~]# ifconfig eth0 Link encap:Ethernet HWaddr 00:1e:c9:24:c9:d1 inet addr:192.168.2.10 Bcast:192.168.2.255 Mask:255.255.255.0 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Interrupt:44 Base address:0xc000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:20 errors:0 dropped:0 overruns:0 frame:0 TX packets:20 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:1348 (1.3 KiB) TX bytes:1348 (1.3 KiB) wlan0 Link encap:Ethernet HWaddr 00:24:2b:c7:74:7e inet addr:10.0.2.218 Bcast:10.0.3.255 Mask:255.255.252.0 inet6 addr: fe80::224:2bff:fec7:747e/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:24154 errors:0 dropped:0 overruns:0 frame:37468 TX packets:677 errors:8 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1670308 (1.5 MiB) TX bytes:140171 (136.8 KiB) Interrupt:19 [root@LTdhcps2:~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 wlan0 10.0.0.0 0.0.0.0 255.255.252.0 U 0 0 0 wlan0 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 [root@LTdhcps2:~]# netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 wlan0 10.0.0.0 0.0.0.0 255.255.252.0 U 0 0 0 wlan0 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
what I've tried to do.
[root@LTdhcps2:~]# route add -net 10.0.0.0 gw 10.0.2.218 dev eth0 SIOCADDRT: Invalid argument [root@LTdhcps2:~]#
Strange error that means nothing =| I googled and find this post: http://www.adminsehow.com/2011/09/gateway-on-a-different-subnet-on-linux/
it says that you have to add a host with the desired gateway IP because the gateway is in a different subnet.
[root@LTdhcps2:~]# route add -host 10.0.2.218/32 dev eth0 [root@LTdhcps2:~]# route add default gw 10.0.2.218
(if I put the dev eth0 at the end of the second command) it gives the SIOCADDRT: No such process error.
as result:
[root@LTdhcps2:~]# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 10.0.2.218 0.0.0.0 UG 0 0 0 wlan0 default 10.0.1.2 0.0.0.0 UG 0 0 0 wlan0 10.0.0.0 * 255.255.252.0 U 0 0 0 wlan0 10.0.2.218 * 255.255.255.255 UH 0 0 0 eth0 192.168.2.0 * 255.255.255.0 U 0 0 0 eth0 [root@LTdhcps2:~]# netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 0.0.0.0 10.0.2.218 0.0.0.0 UG 0 0 0 wlan0 0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 wlan0 10.0.0.0 0.0.0.0 255.255.252.0 U 0 0 0 wlan0 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
But I was unable to ping/traceroute wlan0 using the eth0 interface or its gateway (10.0.1.2)
[root@LTdhcps2:~]# ping -I eth0 10.0.2.218 PING 10.0.2.218 (10.0.2.218) from 192.168.2.10 eth0: 56(84) bytes of data. From 192.168.2.10 icmp_seq=1 Destination Host Unreachable From 192.168.2.10 icmp_seq=2 Destination Host Unreachable [root@LTdhcps2:~]# ping -I eth0 10.0.1.2 PING 10.0.1.2 (10.0.1.2) from 192.168.2.10 eth0: 56(84) bytes of data. From 192.168.2.10 icmp_seq=1 Destination Host Unreachable From 192.168.2.10 icmp_seq=2 Destination Host Unreachable [root@LTdhcps2:~]# traceroute -i eth0 10.0.2.218 traceroute to 10.0.2.218 (10.0.2.218), 30 hops max, 60 byte packets 1 * * * 2 * * * 3 * * * 4 * * *
Sorry for the long post and bad English. I'm facing this problem the holy week =|
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Michael Hampton almost 11 yearsWhat on earth are you trying to do?
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Zoredache almost 11 years
I want to be able to ping and access TFTP through my WIFI interface (wlan0) through my wired interface
- Cannot parse, does not compute. Please restate. -
MaikoID almost 11 yearsIts a long history. But for solve my problem I need route my wired connection through my wifi connection using my linux server as a router. eg. PC1 need to ping another PC that is connected by wireless in the server. Its not that hard to explain, what I need is the route between the two interfaces. Maybe because my English level I couldn't do it properly.
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tripleee almost 4 yearsFor what it's.worth, MacOS
ping
has a-b
option which allows you to select an interface. The man page says this is an Apple addition, so I guess it's not supported on other BSD-based systems.