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On 12/10/2010 10:40 AM, Tom H wrote:
<blockquote
cite="mid:AANLkTimUTt8PZ6jpXTRGV7ET5XxFYcm-Qr40c1JYUxNW@mail.gmail.com"
type="cite">
<pre wrap="">On Fri, Dec 10, 2010 at 8:43 AM, Steve Clark <a class="moz-txt-link-rfc2396E" href="mailto:sclark@netwolves.com"><sclark@netwolves.com></a> wrote:
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<pre wrap="">
I have a confusing problem. I have two centos 5,5 boxes. Both have
sudo.i386 1.7.2p1-9.el5_5
installed
I am using the same sudoers file, but the one on box A keeps trying to do
DNS lookups while the one on box B does not. How do I disable this DNS
lookup?
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</pre>
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<br>
<blockquote
cite="mid:AANLkTimUTt8PZ6jpXTRGV7ET5XxFYcm-Qr40c1JYUxNW@mail.gmail.com"
type="cite">
<pre wrap="">Do both hosts have their hostnames in "/etc/hosts"?
Do both hosts have "hosts: files dns" in "/etc/nsswitch.conf"?
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</pre>
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<br>
strace shows the DNS lookup.<br>
<br>
I have resolved the problem as far why they behaved differently.<br>
Someone had put an entry in /etc/resolv.conf when normally we run our<br>
own nameserver at 127.0.0.1.<br>
Putting a hostname and address in the /etc/hosts also fixed the problem.
<br>
<br>
But I still don't understand why it wants to do a DNS lookup when I
don't<br>
have<br>
Defaults fqdn<br>
in the sudoers file.<br>
<br>
Again here is part of an strace of sudo cat /etc/rc.local;<br>
<br>
...<br>
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 4<br>
connect(4, {sa_family=AF_INET, sin_port=htons(53),
sin_addr=inet_addr("127.0.0.1")}, 28) = 0<br>
fcntl64(4, F_GETFL) = 0x2 (flags O_RDWR)<br>
fcntl64(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0<br>
gettimeofday({1292009049, 862615}, NULL) = 0<br>
poll([{fd=4, events=POLLOUT}], 1, 0) = 1 ([{fd=4, revents=POLLOUT}])<br>
send(4, "\206r\1\0\0\1\0\0\0\0\0\0\5Z7070\tnetwolves\3com"..., 37,
MSG_NOSIGNAL) = 37<br>
poll([{fd=4, events=POLLIN}], 1, 5000) = 1 ([{fd=4, revents=POLLIN}])<br>
ioctl(4, FIONREAD, [86]) = 0<br>
recvfrom(4, "\206r\205\203\0\1\0\0\0\1\0\0\5Z7070\tnetwolves\3com"...,
1024, 0, {sa_family=AF_INET, sin_port=htons(53),
sin_addr=inet_addr("127.0.0.1")}, [16]) = 86<br>
close(4) = 0<br>
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 4<br>
connect(4, {sa_family=AF_INET, sin_port=htons(53),
sin_addr=inet_addr("127.0.0.1")}, 28) = 0<br>
fcntl64(4, F_GETFL) = 0x2 (flags O_RDWR)<br>
fcntl64(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0<br>
gettimeofday({1292009049, 864056}, NULL) = 0<br>
poll([{fd=4, events=POLLOUT}], 1, 0) = 1 ([{fd=4, revents=POLLOUT}])<br>
send(4, "\324\305\1\0\0\1\0\0\0\0\0\0\5Z7070\tnetwolves\3com"..., 51,
MSG_NOSIGNAL) = 51<br>
poll([{fd=4, events=POLLIN}], 1, 5000) = 1 ([{fd=4, revents=POLLIN}])<br>
ioctl(4, FIONREAD, [100]) = 0<br>
recvfrom(4,
"\324\305\205\203\0\1\0\0\0\1\0\0\5Z7070\tnetwolves\3com"..., 1024, 0,
{sa_family=AF_INET, sin_port=htons(53),
sin_addr=inet_addr("127.0.0.1")}, [16]) = 100<br>
close(4) = 0<br>
readlink("/proc/self/exe", "/usr/bin/sudo"..., 4095) = 13<br>
<br>
<br>
<br>
<br>
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<br>
<div class="moz-signature">-- <br>
Stephen Clark<br>
<b>NetWolves</b><br>
Sr. Software Engineer III<br>
Phone: 813-579-3200<br>
Fax: 813-882-0209<br>
Email: <a class="moz-txt-link-abbreviated" href="mailto:steve.clark@netwolves.com">steve.clark@netwolves.com</a><br>
<a class="moz-txt-link-freetext" href="http://www.netwolves.com">http://www.netwolves.com</a><br>
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