Can't ping when dns is running

[Kevin Darcy]

Perhaps a misconfigured named is flooding your link with UDP packets???


- Kevin

Kristina Stoeva wrote:

> My problem is that I cannot ping on IP addresses when 'named' is running =
> not on domain names! If 'named' is not running I can ping on IP address to =
> any machine available in the Internet. I can ping to any domain name =
> address if I point the box to a working Name Server.=20
> I don't have /etc/route.conf file. My routing tables are perfect.
>
> Destination     Gateway         Genmask         Flags Metric Ref    Use =
> Iface
> xx.xx.xx.xx    0.0.0.0         255.255.255.255  UH    0      0        0 =
> eth0
> xx.xx.xx.0    0.0.0.0         255.255.255.224  U     0      0        0 =
> eth0
> 127.0.0.0       0.0.0.0         255.0.0.0        U     0      0        0 =
> lo
> 0.0.0.0         xx.xx.xx.xx   0.0.0.0          UG    0      0        0 =
> eth0
>
> Only if I start 'named' with no zone files the machine would have problem =
> finding it's default route, it finds it eventually. If I run 'named' with =
> zone file, I can ping on IP all the machines in the zone. BUT when I =
> decide to ping outside it's not finding the route even though the routing =
> table is perfect. Actually some of the pings return, I get about 90% =
> placket loss.
> What is a mystery for me is WHY the running of 'named' affects the ability =
> of pinging on IP?? They are on entirely different layers!=20
>
> On 8/16/2000, AL9000 <al9000 at programmer.net> wrote:
> >
> >Kristina Stoeva wrote:
> >>=20
> >> Hi,
> >> I did a fresh Redhat 6.2 'server' install today with bind-8.2.2_P5-9=20
> >. '
> >> named' is not running, it doesn't start by default. I can ping=20
> >on IP=20
> >> address wherever I want.
> >
> >At that time you were using /etc/hosts and /etc/route.conf. Could=20
> >you
> >resolve any external names or only ping by address?
> >
> >> Then I start '/etc/rc.d/init.d/named start' without any configuration
> >> files set up. The machine cannot find it's default route! I can't=20
> >ping on
> >> IP anywhere. It finds the default route eventually after minutes=20
> >of
> >> looking up.
> >
> >The default config file was a sample (at least in 6.1) and not for=20
> >use
> >without editing. It's quite convoluted.
> >
> >> Then I set up the configuration files for one domain, let's say=20
> >cesoft.com.
> >
> >Using a config tool like linuxconf? Did route.conf get changed?
> >
> >>  Now I can ping on IP to any machine in cesoft.com. I still can't=20
> >ping
> >> anywhere in the Internet, on IP of course.
> >
> >I'm not sure if you can still ping using ip numbers. If not, check=20
> >your
> >routing tables - use '/sbin/route -n' to make sure the config scripts
> >didn't cut you off. If your machine is a gateway the output should=20
> >look
> >something like this (the xx addresses are external, interfaces could=20
> >be
> >different).
> >
> >Kernel IP routing table
> >Destination     Gateway         Genmask         Flags Metric Ref=20
> >   Use
> >Iface
> >xx.xx.xx.xx     0.0.0.0         255.255.255.255 UH    0      0  =20
> >     0
> >eth1
> >192.168.0.0     0.0.0.0         255.255.0.0     U     0      0  =20
> >     0
> >eth0
> >127.0.0.0       0.0.0.0         255.0.0.0       U     0      0  =20
> >     0
> >lo
> >0.0.0.0         xx.xx.xx.xx     0.0.0.0         UG    0      0  =20
> >     0
> >eth1
> >
> >> I really hope someone comes up with a hint.
> >> Kristina
> >
> >Hope this helps,
> >AL
> >
> >
> >
> >