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raj.darkmystery 12-23-2009 04:42 AM

destination host unreachable.. while its reachable for first few minutes
 
Hi guys..!!
I am a new user for Ubuntu machine... and i am facing a problem in network connectivity please help me out.
I got one D-link router with one ISP and 2nd Pronet ADSL2 router.. right now i am using 2nd ISP through pronet router by addressing to DHCP settings for 2nd ISP.. when i switch it on 1st ISP then for first few minutes it works fine but then it becomes unreachable :o

I have restarted D-link router several times but again after few minutes it ends in destination unreachable... any possible cause and guidance for overcoming this problem? m nt gating what to do coz, as its reachable initially when restarted means physical connections are fine and working properly... any help??

gregorian 12-23-2009 09:10 PM

Post the result of route

worm5252 12-23-2009 10:19 PM

When it becomes unreachable can you do the following and post the results

Code:

ifconfig
Code:

route
Code:

ping 127.0.0.1
Code:

ping google.com
Code:

ping 74.125.45.105

raj.darkmystery 12-24-2009 01:43 AM

this is the ping reply after 5-10min connectivity

Code:

test@test-desktop:~$ ping 192.168.1.3
PING 192.168.1.3 (192.168.1.3) 56(84) bytes of data.
From 192.168.1.8 icmp_seq=2 Destination Host Unreachable
From 192.168.1.8 icmp_seq=3 Destination Host Unreachable
From 192.168.1.8 icmp_seq=4 Destination Host Unreachable
From 192.168.1.8 icmp_seq=5 Destination Host Unreachable
From 192.168.1.8 icmp_seq=6 Destination Host Unreachable
From 192.168.1.8 icmp_seq=7 Destination Host Unreachable
From 192.168.1.8 icmp_seq=8 Destination Host Unreachable
From 192.168.1.8 icmp_seq=9 Destination Host Unreachable
From 192.168.1.8 icmp_seq=10 Destination Host Unreachable
^C
--- 192.168.1.3 ping statistics ---
12 packets transmitted, 0 received, +9 errors, 100% packet loss, time 11024ms
, pipe 4
test@test-desktop:~$



ifconfig :
Code:

test@test-desktop:~$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:24:01:08:85:66
          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:19 Base address:0x4c00

eth1      Link encap:Ethernet  HWaddr 00:24:01:05:85:9b
          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:18 Base address:0x8800

eth2      Link encap:Ethernet  HWaddr 00:26:18:40:e8:c1
          inet addr:192.168.1.8  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::226:18ff:fe40:e8c1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:365465 errors:0 dropped:0 overruns:0 frame:0
          TX packets:339818 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:130778908 (130.7 MB)  TX bytes:76585046 (76.5 MB)
          Interrupt:27 Base address:0x4000

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:104821 errors:0 dropped:0 overruns:0 frame:0
          TX packets:104821 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:15330565 (15.3 MB)  TX bytes:15330565 (15.3 MB)


route:
Code:

test@test-desktop:~$ route
Kernel IP routing table
Destination    Gateway        Genmask        Flags Metric Ref    Use Iface
192.168.1.0    *              255.255.255.0  U    1      0        0 eth2
link-local      *              255.255.0.0    U    1000  0        0 eth2
default        192.168.1.3    0.0.0.0        UG    0      0        0 eth2
default        192.168.1.1    0.0.0.0        UG    0      0        0 eth2


ping:
Code:

test@test-desktop:~$ ping 127.0.0.1
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.024 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.036 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.029 ms
64 bytes from 127.0.0.1: icmp_seq=4 ttl=64 time=0.031 ms
64 bytes from 127.0.0.1: icmp_seq=5 ttl=64 time=0.036 ms
64 bytes from 127.0.0.1: icmp_seq=6 ttl=64 time=0.032 ms
64 bytes from 127.0.0.1: icmp_seq=7 ttl=64 time=0.031 ms
^C
--- 127.0.0.1 ping statistics ---
7 packets transmitted, 7 received, 0% packet loss, time 6000ms
rtt min/avg/max/mdev = 0.024/0.031/0.036/0.005 ms

ping google.com
Quote:

test@test-desktop:~$ ping google.com
PING google.com (74.125.19.106) 56(84) bytes of data.
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=1 ttl=44 time=519 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=2 ttl=44 time=763 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=3 ttl=44 time=744 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=4 ttl=44 time=520 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=5 ttl=44 time=530 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=6 ttl=44 time=760 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=7 ttl=44 time=744 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=8 ttl=44 time=739 ms
64 bytes from nuq04s01-in-f106.1e100.net (74.125.19.106): icmp_seq=9 ttl=44 time=528 ms
^C
--- google.com ping statistics ---
9 packets transmitted, 9 received, 0% packet loss, time 8227ms
rtt min/avg/max/mdev = 519.687/650.195/763.880/112.397 ms
Code:

test@test-desktop:~$ ping 74.125.45.105
PING 74.125.45.105 (74.125.45.105) 56(84) bytes of data.
64 bytes from 74.125.45.105: icmp_seq=1 ttl=43 time=313 ms
64 bytes from 74.125.45.105: icmp_seq=2 ttl=43 time=313 ms
64 bytes from 74.125.45.105: icmp_seq=3 ttl=43 time=327 ms
64 bytes from 74.125.45.105: icmp_seq=4 ttl=43 time=310 ms
64 bytes from 74.125.45.105: icmp_seq=5 ttl=43 time=316 ms
64 bytes from 74.125.45.105: icmp_seq=6 ttl=43 time=336 ms
^C
--- 74.125.45.105 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 5005ms
rtt min/avg/max/mdev = 310.155/319.583/336.438/9.319 ms



problem is i am able to ping and connect over internet through another gateway as well as through 1.3 gateway but after 5 - 10 min this gateways goes down.. please help me for resolving this issue

gregorian 12-24-2009 04:28 AM

Those are the results of route after it goes down or before it goes down?

raj.darkmystery 12-24-2009 04:37 AM

after it goes down

raj.darkmystery 12-24-2009 04:38 AM

after that i need to change pronet routers DHCP so that i can change default gateway and can access internet... :(

gregorian 12-24-2009 05:39 AM

I have a feeling I know the solution to your problem. I faced the same problem, but it never connected in the first place.

route add default gw <your ip> (Assuming you have an ip. Check with ifconfig. Enter that ip if it's there)
route add default gw <your gateway>

I will elaborate if it works.

raj.darkmystery 12-24-2009 06:33 AM

no its still unreachable.. i have added both routers ip as default gateway and now added machines ip also as a def gw... 1 point i just noticed that all the lights of D-link router are constantly in on condition while normally they are supposed to be in blinking mode... is that any problem with router itself? but if the problem is with router then how come initially it allows the connection?

gregorian 12-24-2009 06:34 AM

Did you add your own address before adding the router's address? The order is important.

raj.darkmystery 12-24-2009 01:10 PM

no i have added both def gws first n then after concerning here hv added my machines ip as a def gw.. :-o shd i supposed to change tht order? n if yes then how? coz i dnt know h to change tht order.. :'(

gregorian 12-24-2009 02:13 PM

Easiest way is to restart, wait for it to fail, and then add in order. Those additions were temporary so they'll go when you restart.

raj.darkmystery 12-26-2009 01:22 AM

have tried this also... but it goes down after some time.. :(

gregorian 12-26-2009 02:30 AM

After it disconnects, did you follow the steps, see it connect for the second time and then watch it go down?

AwesomeMachine 12-26-2009 02:55 AM

DSL internet is supposed to disconnect if it isn't active. If you reconnect, it should work again. If you are using a web browser, surfing the web, the dsl carrier probably wont drop the connection. If it does, call the isp. DSL is not always on. When the dsl drops, it might hang the router. This would make reconnecting impossible without booting the router.


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