DNS lookup occurs even with noconn
Hi all,
I have databases and webpages in my hosts.cfg like this..
0.0.0.0 Oracle_Enterprise_Manager # prefer noping noconn https://ictoem01.stanwell.com:7801/em/console # Obviously a web page
0.0.0.0 soapro # prefer noconn # This is an oracle database which I have tests sent to.
What I find is that even with noconn, it still attempts to resolve the server name ie Oracle_Enterprise_Manager
I have managed to fix this by modifying xymonnet.c on line 839
From this...
if (!h->testip && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
to this
if (!h->testip && !h->noconn && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
Any comments or possible breaking of Xymon??
If my interpretaion is what is expected for the noconn test maybe Henrik could put this in as a bug fix :)
Thanks
Alan Ford Senior Database Administrator Com Serv - Information Communications and Technology Stanwell Corporation Limited
www.stanwell.com<http://www.stanwell.com>
This email is to be read subject to the email disclaimer located at http://www.stanwell.com/email-disclaimer.aspx
What if you add "testip"?
On Fri, May 11, 2012 at 10:21 AM, FORD Alan <Alan.FORD at stanwell.com> wrote:
Hi all,****
I have databases and webpages in my hosts.cfg like this..****
**0.0.0.0 ** Oracle_Enterprise_Manager # prefer noping noconn https://ictoem01.stanwell.com:7801/em/console # Obviously a web page****
**0.0.0.0 **soapro # prefer noconn # This is an oracle database which I have tests sent to.****
What I find is that even with noconn, it still attempts to resolve the server name ie Oracle_Enterprise_Manager****
I have managed to fix this by modifying xymonnet.c on line 839****
From this…****
if (!h->testip && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);****
to this****
if (!h->testip && !h->noconn && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);****
Any comments or possible breaking of Xymon??****
If my interpretaion is what is expected for the noconn test maybe Henrik could put this in as a bug fix J****
Thanks****
*Alan Ford*
*Senior Database Administrator*
*Com Serv - Information Communications and Technology*
*Stanwell Corporation Limited*
www.stanwell.com****
This email is to be read subject to the email disclaimer located at http://www.stanwell.com/email-disclaimer.aspx
Xymon mailing list Xymon at xymon.com http://lists.xymon.com/mailman/listinfo/xymon
Hmm... Maybe. Will have to try it :)
It would have to be something like this then
0.0.0.0 soapro # testip noconn
Seems a bit counter intuitive... lol
From: Jeremy Laidman [mailto:jlaidman at rebel-it.com.au] Sent: Friday, 11 May 2012 3:49 PM To: FORD Alan Cc: xymon at xymon.com Subject: Re: [Xymon] DNS lookup occurs even with noconn
What if you add "testip"? On Fri, May 11, 2012 at 10:21 AM, FORD Alan <Alan.FORD at stanwell.com<mailto:Alan.FORD at stanwell.com>> wrote: Hi all,
I have databases and webpages in my hosts.cfg like this..
0.0.0.0 Oracle_Enterprise_Manager # prefer noping noconn https://ictoem01.stanwell.com:7801/em/console # Obviously a web page
0.0.0.0 soapro # prefer noconn # This is an oracle database which I have tests sent to.
What I find is that even with noconn, it still attempts to resolve the server name ie Oracle_Enterprise_Manager
I have managed to fix this by modifying xymonnet.c on line 839
From this...
if (!h->testip && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
to this
if (!h->testip && !h->noconn && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
Any comments or possible breaking of Xymon??
If my interpretaion is what is expected for the noconn test maybe Henrik could put this in as a bug fix :)
Thanks
Alan Ford Senior Database Administrator Com Serv - Information Communications and Technology Stanwell Corporation Limited
www.stanwell.com<http://www.stanwell.com>
This email is to be read subject to the email disclaimer located at http://www.stanwell.com/email-disclaimer.aspx
Xymon mailing list Xymon at xymon.com<mailto:Xymon at xymon.com> http://lists.xymon.com/mailman/listinfo/xymon
Hmm... Maybe. Will have to try it :)
It would have to be something like this then
0.0.0.0 soapro # testip noconn
Seems a bit counter intuitive... lol
Don't forget that xymon does more than just ping test (which is all 'noconn' modifies). There are a lot of scenarios where ICMP traffic is blocked but you'll still be able to hit --thus, test-- port 80 or some other service.
For those hosts, xymon still needs to be able to look up the IP address if all it has is a name, so if you want to prevent lookup attempts on the fake name you're going to need both tags.
Think of "testip" as "doesnotresolve"
HTH,
-jc
Ok I finally got round to testing it.
To stop DNS lookup on a made up client name you need...
0.0.0.0 soapro # testip noconn
Sweet!!
Thanks all!!
From: xymon-bounces at xymon.com [mailto:xymon-bounces at xymon.com] On Behalf Of FORD Alan Sent: Friday, 11 May 2012 3:58 PM To: 'Jeremy Laidman' Cc: xymon at xymon.com Subject: Re: [Xymon] DNS lookup occurs even with noconn
Hmm... Maybe. Will have to try it :)
It would have to be something like this then
0.0.0.0 soapro # testip noconn
Seems a bit counter intuitive... lol
From: Jeremy Laidman [mailto:jlaidman at rebel-it.com.au] Sent: Friday, 11 May 2012 3:49 PM To: FORD Alan Cc: xymon at xymon.com<mailto:xymon at xymon.com> Subject: Re: [Xymon] DNS lookup occurs even with noconn
What if you add "testip"? On Fri, May 11, 2012 at 10:21 AM, FORD Alan <Alan.FORD at stanwell.com<mailto:Alan.FORD at stanwell.com>> wrote: Hi all,
I have databases and webpages in my hosts.cfg like this..
0.0.0.0 Oracle_Enterprise_Manager # prefer noping noconn https://ictoem01.stanwell.com:7801/em/console # Obviously a web page
0.0.0.0 soapro # prefer noconn # This is an oracle database which I have tests sent to.
What I find is that even with noconn, it still attempts to resolve the server name ie Oracle_Enterprise_Manager
I have managed to fix this by modifying xymonnet.c on line 839
From this...
if (!h->testip && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
to this
if (!h->testip && !h->noconn && (dnsmethod != IP_ONLY)) add_host_to_dns_queue(h->hostname);
Any comments or possible breaking of Xymon??
If my interpretaion is what is expected for the noconn test maybe Henrik could put this in as a bug fix :)
Thanks
Alan Ford Senior Database Administrator Com Serv - Information Communications and Technology Stanwell Corporation Limited
www.stanwell.com<http://www.stanwell.com>
This email is to be read subject to the email disclaimer located at http://www.stanwell.com/email-disclaimer.aspx
Xymon mailing list Xymon at xymon.com<mailto:Xymon at xymon.com> http://lists.xymon.com/mailman/listinfo/xymon
participants (3)
-
Alan.FORD＠stanwell.com
-
cleaver＠terabithia.org
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jlaidman＠rebel-it.com.au