[Crash-utility] netdump starting problem

[Jeff Moyer]

Dave Anderson <anderson at redhat.com> writes:

> ----- "Anirudh Srinivasan" <srianirudh at gmail.com> wrote:
>
>> hello friends,
>> 
>> I was setting up netdump server in my workplace. I followed the
>> following procedure:
>> 
>> Server Configuration:
>> 
>>     1.
>> Verify that the netdump server is installed: rpm -q netdump-server .
>> If it is not installed, install it by running the command: up2date
>> netdump-server .
>>     2.
>> After the netdump server package is installed change the password for
>> the "netdump" user to something that you know: passwd netdump
>>     3.
>> Enable the netdump server: chkconfig netdump-server on
>>     4.
>> Start the netdump server: service netdump-server start
>> 
>> Client Configuration:
>> 
>>     1.
>> Verify that the netdump client is installed: rpm -q netdump . If it is
>> not installed, install it by running the command: up2date netdump .
>>     2.
>> Edit /etc/sysconfig/netdump and add the following line:
>> NETDUMPADDR=192.168.0.5 **192.168.0.5 should be changed to the ip
>> address of the netdump server.
>>     3.
>> Enter the following command and give the netdump password when
>> prompted: service netdump propagate
>>     4.
>> Enable the netdump client: chkconfig netdump on
>>     5.
>> Start the netdump client: service netdump start
>> 
>> Now after doing this i get the following message:
>> 
>> # service netdump start
>> netdump: cannot arp <ipaddress>
>> netdump: cannot find <ipaddress>in arp cache
>> netdump: can't resolve <ipaddress> MAC address
>> netdump server address resolution [FAILED]
>> 
>> 
>> What could be the reason for this ? How could i solve this?
>
>
> There's a couple other netdump masters on this list who can
> hopefully help you out, but I'd start by taking a look at the
> "print_address_info()" function in the /etc/rc.d/init.d/netdump
> script.  It does a traceroute of your configured netdump-server
> IP to get the MAC address of the gateway if needed: 
>
>     # the needed MAC address is directly associated with the host
>     # IP address only if client and server are on the same subnet
>     # if not, the needed MAC address is that of the gateway;
>     # either way, this will be the first IP address from traceroute
>     trc_output="$(traceroute -i $DEV -n -m 1 $host_ip 2> /dev/null)"
>     if [ $? -eq 0 ]; then
>         trc_output="$(echo $trc_output | grep '^1 ' | awk '{print $2}')"
>
>         for line in $trc_output; do mac_ip=$line; done
>     else
>         echo "$prog: cannot traceroute $host_ip on interface $DEV" 1>&2
>         mac_ip=$host_ip
>     fi
>
> And then based upon what it got back, the subsequent arping error 
> message that you're seeing is generated:
>
>     # If the server is on the same subnet as the client, but is currently
>     # offline, then the first hop will show up as our local address.  This
>     # would not be a working setup, so we set mac_ip to the server ip.
>     localaddr=$(ip_of_device $DEV)
>     [ "mac_ip" = "$localaddr" ] && mac_ip=$host_ip
>
>     arping -c 1 -I $DEV $mac_ip &> /dev/null
>     [ $? -ne 0 ] && echo "$prog: cannot arp $mac_ip on $DEV" 1>&2
>
> So you can do the traceroute and arping commands above yourself to find out
> exactly where it's having a problem.

A common problem is not specifying the DEV= line in
/etc/sysconfig/netdump.  We need to know which interface netdump is
configured for.

Cheers,
Jeff