ping does not resolve the host - always appends a domain
Solution 1
You may try
search . domainname.ext
to see if just adding the '.' works. Also
$ ping vanja.
would give you some clues.
Solution 2
Your resolver search path needs to be set.
In /etc/resolv.conf, add the line:
search domainname.ext
(Of course, replace domainname.net
above with your domain name).
This will ensure that ping hostname
also looks up hostname.domainname.ext
. Note that, you can add multiple domain names to the search path if you want.
Related videos on Youtube
Comments
-
dma_k over 1 year
The problem seems to be relatively easy, but I can't find good solution.
Configuration
I have local DHCP and DNS server running on ADSL router. It assigns IP addresses to local hosts and also keeps DNS records for assigned IPs.
This modem also registers itself via DynDNS services.
Let's assume I have no control over this modem, as it serves several groups.
Problem
When I look the host via
nslookup
it works fine:$ nslookup vanja Server: 192.168.1.1 Address: 192.168.1.1#53 Name: vanja Address: 192.168.1.12
but with
ping
it fails:$ ping vanja ping: unknown host vanja
This happens, because
ping
appends the local domain to the host, but DNS server does not know this domain (and I have no ways to set it), see strace output:$ strace ping vanja open("/lib/i686/cmov/libnss_dns.so.2", O_RDONLY) = 4 stat64("/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=23, ...}) = 0 socket(PF_INET, SOCK_DGRAM|SOCK_NONBLOCK, IPPROTO_IP) = 4 connect(4, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("192.168.1.1")}, 28) = 0 send(4, "\377N\1\0\0\1\0\0\0\0\0\0\5vanja\10dynalias\3com\0"..., 36, MSG_NOSIGNAL) = 36 recvfrom(4, "\377N\201\203\0\1\0\0\0\1\0\0\5vanja\10dynalias\3com\0"..., 1024, 0, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("192.168.1.1")}, [16]) = 97
Also note that
nslookup vanja.dynalias.com
will also fail on the same reason: DNS only maps dynamically assigned IPs to short PC names (which are passed from MS Windows workstations).When I set the hostname to name without domain (
# hostname centurion
) ping magically starts working, but I cannot leave hostname not in FQDN form, as otherwise it may confuse apache & postfix or break other things.Question: How can I make
ping
working together with having hostname in FQDN form?Note: My attempts to play with
search
anddomain
options of/etc/resolv.conf
haven't succeeded. My goal was to force NSS library not to append domain name to the passed argument, or, better, make two tries: without and with domain appended.Relative settings
$ hostname centurion.dynalias.com $ cat /etc/resolv.conf nameserver 192.168.1.1 $ grep hosts /etc/nsswitch.conf hosts: files dns
-
Admin about 14 yearsSeems like this is a better question for serverfault.com
-
Admin about 14 years@Jeremy: Maybe, but I like very much the community and this resource, that's why I would like to contribute also with well-described question :)
-
-
Alex K about 14 yearsSorry, that does not work. The problem is that appending a domain name leads to "host not found". It would be nice, if I could say "search '', 'domainname.ext'" or (my dreams) "search . domainname.net". I've updated the problem description to state this explicitly, so you can update your reply, if you have a solution, or withdraw it, because it is not solving a problem at all.
-
Kumar Kush about 14 years+1 One comment: in order to 'ping vanja.' you don't need to add anything to '/etc/resolv.conf', as you tell explicitly, that you deal with 1st level name. Thanks, that helps.