# broken ping [SOLVED]

## Darkshine

Last few days ping program have worked strange. The ping output looks like:

```
...

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12709 ttl=55 time=85.2 ms

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12710 ttl=55 time=90.1 ms

wrong data byte #36 should be 0x24 but was 0x0

#8      8 9 a b c d e f 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 0 0 0 0

#40     0 0 0 0 0 0 0 0 0 0 0 0 34 35 36 37

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12711 ttl=55 time=84.7 ms

wrong data byte #36 should be 0x24 but was 0x0

#8      8 9 a b c d e f 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 0 0 0 0

#40     0 0 0 0 0 0 0 0 0 0 0 0 34 35 36 37

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12712 ttl=55 time=85.1 ms

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12713 ttl=55 time=85.4 ms

64 bytes from sitecheck.opera.com (195.189.143.147): icmp_seq=12714 ttl=55 time=97.4 ms

...

```

I've googled by these error messages, but I have not found a solution or cause of the above errors. It seems the errors don't affect anything except my dyndns.com client (called net-dns/ddclient - "Perl updater client for dynamic DNS services"): it seems ddclient cannot send my IP to the dyndns.com server.

In the /var/log/messages file I see a lot of messages about wrong checksum:

```
Apr  9 23:24:45 primula UDP: bad checksum. From 220.237.82.48:57549 to 95.132.112.195:1025 ulen 111
```

I have a four network interfaces on this computer: lo, eth0, eth1 and ppp0 (ppp0 over eth1). ping works fine with all of them except ppp0.

```
eth1      Link encap:Ethernet  HWaddr 00:53:45:00:00:00

          inet addr:192.168.1.3  Bcast:192.168.1.255  Mask:255.255.255.0

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:6959652 errors:0 dropped:0 overruns:0 frame:0

          TX packets:1160112 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:1015253998 (968.2 MiB)  TX bytes:608977880 (580.7 MiB)

          Interrupt:12 Base address:0xc000

ppp0      Link encap:Point-to-Point Protocol

          inet addr:95.132.112.195  P-t-P:195.5.5.184  Mask:255.255.255.255

          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1492  Metric:1

          RX packets:1218016 errors:0 dropped:0 overruns:0 frame:0

          TX packets:1155655 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:3

          RX bytes:643952361 (614.1 MiB)  TX bytes:583230870 (556.2 MiB)

```

```
23:14:44 [1]root@primula:~>ping -V

ping utility, iputils-sss20071127

```

The only manipulations I did few days ago which can be related to the problem is a changing a hostname in the /etc/conf.d/hostname. Yesterday I rolled back to the old hostname, even rebooted after those changes, but the problem still occurs. 

please, adviseLast edited by Darkshine on Fri Apr 10, 2009 6:32 pm; edited 1 time in total

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## poly_poly-man

does ping -s 0 host work?

it looks like somewhere along the line, your packets (not just ping ones, but anything udp/icmp) are being mutilated... could be by your computer, your router/connection to the internet or your isp.

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## Darkshine

 *poly_poly-man wrote:*   

> does ping -s 0 host work?

 

I have not changed anything today, but now it works fine: ping works correct and there are no new "chksum failed" messages in the /var/log/messages

 *poly_poly-man wrote:*   

> it looks like somewhere along the line, your packets (not just ping ones, but anything udp/icmp) are being mutilated... could be by your computer, your router/connection to the internet or your isp.

 

Probably you're right, it seems the problem was on the ISP side.

thanks

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