Networking :: BIND9 SLOW Ping When Ping By Hostname
Feb 1, 2011
I just installed my first EVER bind DNS server. I am running bind9 on Ubuntu 10.04. Everything seems to be working great except one thing: If I ping a host that I have set up in bind by its HOSTNAME the pings take 5-6 seconds to reply/print to the screen between each echo response. If I ping by the host's IP address, they echo back very quickly.
I have read that IPv6 can cause this, but I have disabled it in /etc/sysctl.conf and the problem still exists.
I know everyone says this can't be a DNS issue, but this never was an issue with dnsmasq (which i was using prior), and it doesn't make sense that the ping are ONLY slow when pinging by hostname and not IP.
Ping by hostname - there is a 5-6 second delay between each one of the responses:
Ping by IP - the responses come VERY quickly one after the other:
I have a network of 2 WinXP machines and one linux box. I have fiddled around with the settings as you do when learning. The network is working. The network neighbourhood on the WinXP machines recognise the linux box and vice versa, (the linux Places|Network recognises the 2 WinXP). I can Ping the linux box using its hostname from a WinXp. But I cannot do the reverse. I get an 'unknown host' response. I can ping the linux to itself using its hostname.
I'm having an issue on two Fedora Core 13 machines where I can ping others by hostname, but the hostname resolution fails whenever I use ssh/scp/vnc/etc. I can still do these things by IP address, just not by hostname. RHEL5.3 machines on the same network with the same configuration do not seem to have this problem.
Here's the not-so-quick-and-dirty description of the situation:
I know that there is a virtual router at 192.168.31.1 and another at 192.168.30.1. I also know that there is another network (let's call it 18.104.22.168) and on that network lies a number of resources. By nature of this configuration, any machine on 22.214.171.124 can be accessed by any 192.168.x.x, but not the other way around. Beyond that is out of my hands and currently out of my scope of knowledge.
I have a dnsmasq server on 126.96.36.199 that operates as a secondary nameserver, another machine out of my sphere of influence is the primary nameserver (188.8.131.52).
The secondary nameserver on 184.108.40.206 holds the hostnames of our development machines. The problem is that in some cases, while I can ping by hostname all day long, services such as ssh, scp, vncviewer, etc all fail to resolve the hostname. In other cases I can do all of these things.
Every machine has an equivalent resolv.conf:
As an example, I will show the output of a handful of my development machines:
I also included columbia as a one-way test -- even though it cannot access 30.x or 31.x, they can access it:
columbia -- physical machine, Red Hat Enterprise 5.3, IP 192.168.100.200
Okay, so here are the various outputs. Remember, nibbler, discovery, and atlantis can ALL: - Ping by IP address - Ping by hostname - ssh, scp, vnc, etc by IP addess
Additionally, the SERVFAIL reply from 220.127.116.11 is expected since my dnsmasq server is on the secondary server.
Note that the only machine that can both ping and ssh/scp/etc by hostname is nibbler, which also happens to be the only one of the three running RHEL5.3 instead of FC13. Other virtual and physical machines running on the 192.168.31.0 and 192.168.30.0 networks (all running RHEL5.3) work just like nibbler does. So the problem seems to only affect machines running FC13.
Final note: selinux is disabled, iptables is disabled, ip6tables is disabled.
Other than that, discovery is a brand-spanking-new install straight off of the FC13 DVD. atlantis has been around longer, but its just a file server so I haven't done anything too crazy to it.
I have 4 installations of Fedora 14 running on a Win 2008 R2 server in Hyper-V.
When I try to ping my desktop or the host server via the hostname from within any of the Fedora installations, the ping fails. I can ping by IP without issue. Also if I try to ping the VMs from my desktop it fails. I have an XP VM setup that I can ping without issue via hostname and IP.
All of the VMs can access the Internet without issue. I have disabled all firewalls on all systems with no luck. My desktop can ping the Hyper-V server without issue so it would appear that the problem lies with the Fedora installations.
Does anyone have anything I can try to get the name resolution working?
I have a Windows 7 machine that I have an installation of Ubuntu 10.10 via VMware and am having an issue with pinging by hostname thorugh the VM. From the Windows 7 machine I can ping by name without any issue but not with the VM. I have the VM as bridged so it is pulling all the network stuff via DHCP including the correct DNS servers. I can ping all the DNS servers and host without any issue. I have verified my /etc/resolv.conf entries are all correct.
If I run nslookup via the VM it says:
I have also verified that AVAHI is running to cache the DNS stuff and still no success.
At work, I recently installed FreeNAS 0.7.4919 on a computer and set it up to be a samba server. Using a Windows XP Pro SP3 computer on the same subnet as the FreeNAS server, I can ping the FreeNAS server's hostname and it works just fine. However, using an Ubuntu 10.04 computer on the same subnet as the FreeNAS server, I am unable to ping the FreeNAS server's hostname. When I try, it says "ping: unknown host [the FreeNAS server's hostname]". I can ping its IP address just fine, though. Why is it that Windows XP Pro can ping the FreeNAS server's hostname but Ubuntu 10.04 can't?Here's the output of the ifconfig command on the Ubuntu 10.04 computer:
Code: eth0 Link encap:Ethernet HWaddr 00:14:c2:cd:a6:39 inet addr:10.37.74.141 Bcast:10.37.75.255 Mask:255.255.252.0
I have a weird problem since yesterday that I can't solve. I can't ping / ssh my machine anymore using its hostname... says "unknown host", "network unreachable". I have no idea why - it used to work perfectly. I can still ping / ssh using the IP so it must be a problem of hostname not being resolved.
I have a dynamic IP (I'm at work...) but that doesn't seem to be the problem - network manager automatically adds a line in /etc/hosts with <mycurrentip> <hostname> (I checked, it's indeed the IP given by ifconfig and that I can use to ping/ssh).
2nd question: Another computer has a similar problem but slightly different: the hostname is resolved but points to a wrong IP (seen in ping or nslookup), different from what ifconfig returns. As a result, ping times out and ssh says "no route to host".
ever since upgrading from karmic to lucid, i cannot ping fqdn hosts in .local tlds. nslookup & dig work, but most other utilities fail (ping, traceroute, etc...). i know .local is an invalid tld, but apple seems to have made it a defacto standard on private networks, so i'd imagine somebody else has seen this issue before... is there a simple fix that doesn't require managing hosts file entries on a bunch of systems?
I have a windows 7 desktop hardwired to my wireless router and a windows xp laptop connecting wirelessly on the same network. I am able to ping the windows 7 box by its ip address but unable to do so by its hostname. This is very inconvenient since I would like to set up a share by hostname (doesnt change) and not by ip (changes occasionally since its dhcp).
LAN CentOS 5.5 Windows 7 machine (hostname/NETBIOS name: AwesomePC, LAN IP: 192.168.1.20) Workgroup: Cake No WINS server No Domain No AD
From CentOS 5.5, have
# ping AwesomePC
resolve to a ping on 192.168.1.20
# ping AwesomePC
resolves to some random public IP that seems to be coming from my WAN DNS (openDNS) servers
Have edited /etc/nsswitch.conf, edited line: hosts: files wins dns Have edited /etc/resolv.conf, added line: search CAKE Have installed samba (# yum install samba) and run (# service smb start), with /etc/samba/smb.conf, workgroup = CAKE, name resolve order = wins host lmhosts bcast
Does # ping even care about samba? How can I get this to work?
I can't ping by netbios name or fully qualified domain name, BUT nmblookup works just fine. I know it's a dns problem(s) I just don't know what or how to fix it. I'm very new to all of this(networking, domain administration, posting on forums etc) so I hope this is the right way to ask for help here. I've searched around the forums and the internet for a bit but I haven't found a solution to my problem yet.
here is some background on how the network is setup2 different domains sharing the same dhcp scope.
DC for DomainA is running windows 2003 std DC for DomainB is running windows 2008 sbs DC-A has ip of 192.168.1.249 DC-B has ip of 192.168.1.3 router is sonicwall (192.168.1.1) DC-A is hosting both DHCP and DNS
there are 25 computers in DomainB and 1 computer (not in domain) with ubuntu 10.04 and Free Open Ghost running on it (dhcp off) all 25 computers can ping the fog server by name (and eachother) all 25 computers pxeboot to fog just fine
As the title suggest, I have downlaoded the latest copy of Ubuntu Server from the ubuntu website.Everything installed fine. DHCP configured ok as far as I can tell. I can ping other machines on my network (which are running Windows) and they can ping the Ubuntu machine and conenct to Apache which is running on it.If I try to ping google.com or any other domain, it gives the correct IP address but gives no response to any pings, dont telnet on port 80 (or any toher potr for that matter) on any machine on the internet. I checked the settings using ifconfig to see what DHCP had assigned, and they matched the windows machines configuration (other than the IP address obvisouly). I tried assigning a static IP, even reserving a particular IP for my NIC.
Whatever I do, i cant connect to any machine outside the network via IP or domain.I have searched everywhere and tried everything i can find on the net but still to no avail.The Windows machines are part of a domain called alcom-uk.local and run off of a Windows Small Business 2003 Server. Not sure if i need to manually setup Ubuntu to connect using a domain or anything.
So, I have an Virtual Machine running CentOS 5.4. It sits behind a hardware firewall which also does NAT'ing. I've set up plenty of these, so I know for sure the firewall and NAT rules are set up correctly. From the host, I can ping anything in my subnet and the gateway. But I can't ping anything else beyond the gateway. I can perform DNS queries and when I try to ping, it finds the appropriate IP address.But from the outside, I can ping the PUBLIC address (It's a 1 public to 1 private address NAT, not 1 public to multiple private). I've tried it with IPTABLES on and off, with no change.
I have Mandriva One 2009.0 (192.168.1.100) on one box and Mandriva Free 2010.0 (192.168.1.118) on the other. I can ping router (192.168.1.1) from both of these boxes but I can't ping one box to the other and the other way around. What's going on?.
Do I have to change some settings in router?. Or is it firewall issue on those two machines?. Both of these boxes are connected by cable. Symbol of the router: TL-WR340G.
So after some period of inactivity, my FC servers with infiniband cards in them seem to go to sleep or something. If I login to the machine and try to ping other machines with IB interfaces, the first request takes much longer than the others. This is not so over Ethernet.
compute-4-12 ~]# ping ib-s0-1 (this is a solaris machine) PING ib-s0-1.local (192.168.1.19) 56(84) bytes of data. 64 bytes from ib-s0-1.168.192.in-addr.arpa (192.168.1.19): icmp_req=1 ttl=255 time=3.64 ms 64 bytes from ib-s0-1.168.192.in-addr.arpa (192.168.1.19): icmp_req=2 ttl=255 time=0.131 ms 64 bytes from ib-s0-1.168.192.in-addr.arpa (192.168.1.19): icmp_req=3 ttl=255 time=0.222 ms
compute-4-08 ~]# ping c4-7 (identical neighboring FC machine) PING compute-4-07.local.local (10.255.255.187) 56(84) bytes of data. 64 bytes from compute-4-07.local.255.10.in-addr.arpa (10.255.255.187): icmp_req=1 ttl=64 time=1.28 ms 64 bytes from compute-4-07.local.255.10.in-addr.arpa (10.255.255.187): icmp_req=2 ttl=64 time=0.108 ms 64 bytes from compute-4-07.local.255.10.in-addr.arpa (10.255.255.187): icmp_req=3 ttl=64 time=0.115 ms 64 bytes from compute-4-07.local.255.10.in-addr.arpa (10.255.255.187): icmp_req=4 ttl=64 time=0.119 ms 64 bytes from compute-4-07.local.255.10.in-addr.arpa (10.255.255.187): icmp_req=5 ttl=64 time=0.180 ms
This issue does not only affect ping. I created a user that mounts his home directory over nfs over infiniband. ssh'ing in takes longer the first time as well. If I ssh with verbosity turned up all the way, I get a brief hang at "we sent a hostbased packet, wait for reply" (this is the primary symptom I'm trying to get rid of since we want home directories over nfs over IB (without the initial delay)).
I have installed a ubuntu 9.10 server to use mostly as a fileserver. When I installed the server I set it up as DHCP and later on I have changed the /etc/network/interfaces file, the /etc/hosts file and the /etc/hostname file. I have the ip 192.168.1.100 set on the server and I can ping and SSH this address. But I can not ping my server by it's hostname enighet. I am setting up a NFS server and I would like to use my servers hostname when I do this. Why can I not ping my server by it's hostname? These are the 3 files I have changed...
Code: johan@enighet:~$ 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
I configure a Linux Suse 10 box, added static IP, DNS (resolv), gateway (routes) but I am not able to ping other servers by name but nslookup works and the server can navigate on internet check below the problematic server is server-host20
Other server can ping that server by name just fine
All my network information by the way my server can ping DNS server by name just ok and as you see nslookup works.
I have connected xp and fedora through crossover cable . xp has ip address 192.168.0.1/24 (manually assigned) fedora has 192.168.0.2/24 with default route equal to 192.168.0.1
I can ping fedora from xp computer but i can't able to ping xp from fedora computer.
I have manully edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file with correct subnet mask and ip address because when i tried to give ip address manully in network manager the subnetmask is replaced with gateway address don't know why.
Now i want to share internet through crossover cable . xp is connected to internet through wireless usb adapeter.
First off I should say that I am a total Linux and Networking Noob. I have used Windows all my life, but I am now trying to get into linux so I have set up an old PC with Fedora.
Currently I only have the Linux Box and a Windows 7 Box and they are both connected to my broadband router. I have set them up with static IP addresses in the router and they can both ping each other by IP address but not hostname. I would like to be able to use hostnames to access each box (e.g. for SSH access and File Sharing). My question is basically how can I do this, what are the options and which is recommended for a small home network?
So far I have been able to set up the linux box to be able to ping the Windows box by hostname by editing the hosts file. Is this the right thing to do? Should I just do this on the Windows box too?
I try to ping with php : exec("ping -n 1 $ip",$output,$retval); it works fine in window. but in linux i got this error : ping: icmp open socket: Operation not permitted are there any ways to solve this ?
This applies to my 2 opensuse PC's, my Windows PC is fine.I can ping a hostname, say "PC1" but I can not ping PC1.domain.local (even the host PC can not ping it's own FQDN). When I ping just the hostname the ping stats even list the FQDN.Onto the next issue, since all my PC's, have the domain prefix domain.local, my Synology can not. I can ping it's IP and that is it. I can resolve it's name with nmblookup just fine tho and that is what is killing me. How is this not resolving.Even weirder, I can browse to "Synology" in Network Servers under places on the slab.