Xymon - smtp 🔗 link

From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Ajay Kumar Talla
Sent: Tuesday, March 27, 2018 12:59 PM
To: xymon at xymon.com
Subject: [Xymon] Xymon - smtp

Hi,

I'm using smtp test in Xymon for monitoring. However sometimes, I'm getting error as connection timed out.  After sometime it is showing as Green(Flapping status)

Could you please, let me know the solution for this.

Thanks,
Ajay

From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Root, Paul T
Sent: Tuesday, March 27, 2018 3:10 PM
To: 'Ajay Kumar Talla'; xymon at xymon.com<mailto:xymon at xymon.com>
Subject: Re: [Xymon] Xymon - smtp

This is a load issue. Sendmail will refuse to process mail messages if the CPU is too busy.

From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Ajay Kumar Talla
Sent: Tuesday, March 27, 2018 12:59 PM
To: xymon at xymon.com<mailto:xymon at xymon.com>
Subject: [Xymon] Xymon - smtp

Hi,

I'm using smtp test in Xymon for monitoring. However sometimes, I'm getting error as connection timed out.  After sometime it is showing as Green(Flapping status)

Could you please, let me know the solution for this.

Thanks,
Ajay
This communication is the property of CenturyLink and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.
This communication is the property of CenturyLink and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.

On 28 March 2018 at 07:27, Ajay Kumar Talla <user-9b7115346c33@xymon.invalid> wrote:

Thank you for the information.

But I don’t see any huge CPU  load on my server for the past 4 hours. But
still SMTP test is flapping.

The screenshot attached says “*connection timedout*” is there a way to
change the time-out setting?


I have the same SMTP test on another server whose Load becomes high at
times, but it’s SMTP remains green.


*From:* Root, Paul T <user-76fdb6883669@xymon.invalid>
*Sent:* Wednesday, March 28, 2018 1:42 AM
*To:* Root, Paul T <user-76fdb6883669@xymon.invalid>; Ajay Kumar Talla <
user-9b7115346c33@xymon.invalid>; xymon at xymon.com
*Subject:* RE: Xymon - smtp

Behalf Of *Root, Paul T
*Sent:* Tuesday, March 27, 2018 3:10 PM
*To:* 'Ajay Kumar Talla'; xymon at xymon.com
*Subject:* Re: [Xymon] Xymon - smtp


This is a load issue. Sendmail will refuse to process mail messages if the
CPU is too busy.

Behalf Of *Ajay Kumar Talla
*Sent:* Tuesday, March 27, 2018 12:59 PM
*To:* xymon at xymon.com
*Subject:* [Xymon] Xymon - smtp


Hi,


I’m using smtp test in Xymon for monitoring. However sometimes, I’m
getting error as connection timed out.  After sometime it is showing as
Green(Flapping status)


Could you please, let me know the solution for this.


Thanks,

Ajay

This communication is the property of CenturyLink and may contain
confidential or privileged information. Unauthorized use of this
communication is strictly prohibited and may be unlawful. If you have
received this communication in error, please immediately notify the sender
by reply e-mail and destroy all copies of the communication and any
attachments.

This communication is the property of CenturyLink and may contain
confidential or privileged information. Unauthorized use of this
communication is strictly prohibited and may be unlawful. If you have
received this communication in error, please immediately notify the sender
by reply e-mail and destroy all copies of the communication and any
attachments.

From: Jeremy Laidman <user-0608abae5e7c@xymon.invalid>
Sent: Wednesday, March 28, 2018 11:30 AM
To: Ajay Kumar Talla <user-9b7115346c33@xymon.invalid>
Cc: Root, Paul T <user-76fdb6883669@xymon.invalid>; xymon at xymon.com
Subject: Re: [Xymon] Xymon - smtp

The default timeout for xymonnet is 10 seconds. The xymonnet command in tasks.cfg can have "--timeout=N" added to adjust timeouts.

Have you tried to connect to the service yourself, using telnet, to see if there is indeed a timeout, and what form it takes? Something like this:

or if you don't have nc or netcat:

$ { printf "mail\r\nquit\r\n"; sleep 1; } | time telnet qts-pro-cm-weber 25

Xymon has more than one form of timeout. I believe if Xymon fails to connect due to a timeout, it will show a different error to what you've seen. In your case, I suspect Xymon has connected, and has issued its commands (mail and quit, from protocols.cfg), and is waiting for "220". If it doesn't get a 220 within 10 seconds, it will timeout the session.

I've seen this type of thing happen when TCP wrappers are used to limit access to a service, or for similar security measures. In these cases, the incoming connection is from a host that the mail server does not know about, and so it attempts to find the hostname by reverse DNS lookup. If DNS is slow or misconfigured on the mail server, the DNS lookup can take 15 seconds to fail. In these cases, a quick fix is to add the Xymon server IP address to the /etc/hosts file on the mail server. A better solution is to fix the DNS.

J


On 28 March 2018 at 07:27, Ajay Kumar Talla <user-9b7115346c33@xymon.invalid<mailto:user-9b7115346c33@xymon.invalid>> wrote:
Thank you for the information.
But I don’t see any huge CPU  load on my server for the past 4 hours. But still SMTP test is flapping.
The screenshot attached says “connection timedout” is there a way to change the time-out setting?

I have the same SMTP test on another server whose Load becomes high at times, but it’s SMTP remains green.

From: Root, Paul T <user-76fdb6883669@xymon.invalid<mailto:user-76fdb6883669@xymon.invalid>>
Sent: Wednesday, March 28, 2018 1:42 AM
To: Root, Paul T <user-76fdb6883669@xymon.invalid<mailto:user-76fdb6883669@xymon.invalid>>; Ajay Kumar Talla <user-9b7115346c33@xymon.invalid<mailto:user-9b7115346c33@xymon.invalid>>; xymon at xymon.com<mailto:xymon at xymon.com>
Subject: RE: Xymon - smtp


https://serverfault.com/questions/119026/question-on-sendmail-daemon-actions-when-load-average-is-too-high<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fserverfault.com%2Fquestions%2F119026%2Fquestion-on-sendmail-daemon-actions-when-load-average-is-too-high&data=user-a75bdc575572@xymon.invalid%7C5184c4e69cfc41d611ff08d5941f037d%7C47049324c4984be5acf70154448a1107%7C1%7C0%7C636577783282992025&sdata=gTT%2BrA7A88BosFDvteurJlcdKSi7XiT1ug6l%2FSd5zPg%3D&reserved=0>;

From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Root, Paul T
Sent: Tuesday, March 27, 2018 3:10 PM
To: 'Ajay Kumar Talla'; xymon at xymon.com<mailto:xymon at xymon.com>
Subject: Re: [Xymon] Xymon - smtp

This is a load issue. Sendmail will refuse to process mail messages if the CPU is too busy.

From: Xymon [mailto:xymon-bounces at xymon.com] On Behalf Of Ajay Kumar Talla
Sent: Tuesday, March 27, 2018 12:59 PM
To: xymon at xymon.com<mailto:xymon at xymon.com>
Subject: [Xymon] Xymon - smtp

Hi,

I’m using smtp test in Xymon for monitoring. However sometimes, I’m getting error as connection timed out.  After sometime it is showing as Green(Flapping status)

Could you please, let me know the solution for this.

Thanks,
Ajay
This communication is the property of CenturyLink and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.
This communication is the property of CenturyLink and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.

wrote:

Thank you Jeremy and Paul for pointing me in the right direction.

As you explained it was due to DNS issue, fixed it by adding the IP’s to
/etc/hosts file


Thanks for your help.


--Aj

*From:* Jeremy Laidman <user-0608abae5e7c@xymon.invalid>
*Sent:* Wednesday, March 28, 2018 11:30 AM
*To:* Ajay Kumar Talla <user-9b7115346c33@xymon.invalid>
*Cc:* Root, Paul T <user-76fdb6883669@xymon.invalid>; xymon at xymon.com
*Subject:* Re: [Xymon] Xymon - smtp


The default timeout for xymonnet is 10 seconds. The xymonnet command in
tasks.cfg can have "--timeout=N" added to adjust timeouts.


Have you tried to connect to the service yourself, using telnet, to see if
there is indeed a timeout, and what form it takes? Something like this:


$ printf "mail\r\nquit\r\n" | time nc ipxdvo.tcif.telstra.com.au

25


or if you don't have nc or netcat:


$ { printf "mail\r\nquit\r\n"; sleep 1; } | time telnet qts-pro-cm-weber 25


Xymon has more than one form of timeout. I believe if Xymon fails to
connect due to a timeout, it will show a different error to what you've
seen. In your case, I suspect Xymon has connected, and has issued its
commands (mail and quit, from protocols.cfg), and is waiting for "220". If
it doesn't get a 220 within 10 seconds, it will timeout the session.


I've seen this type of thing happen when TCP wrappers are used to limit
access to a service, or for similar security measures. In these cases, the
incoming connection is from a host that the mail server does not know
about, and so it attempts to find the hostname by reverse DNS lookup. If
DNS is slow or misconfigured on the mail server, the DNS lookup can take 15
seconds to fail. In these cases, a quick fix is to add the Xymon server IP
address to the /etc/hosts file on the mail server. A better solution is to
fix the DNS.


J


On 28 March 2018 at 07:27, Ajay Kumar Talla <user-9b7115346c33@xymon.invalid> wrote:

Thank you for the information.

But I don’t see any huge CPU  load on my server for the past 4 hours. But
still SMTP test is flapping.

The screenshot attached says “*connection timedout*” is there a way to
change the time-out setting?


I have the same SMTP test on another server whose Load becomes high at
times, but it’s SMTP remains green.


*From:* Root, Paul T <user-76fdb6883669@xymon.invalid>
*Sent:* Wednesday, March 28, 2018 1:42 AM
*To:* Root, Paul T <user-76fdb6883669@xymon.invalid>; Ajay Kumar Talla <
user-9b7115346c33@xymon.invalid>; xymon at xymon.com
*Subject:* RE: Xymon - smtp

<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fserverfault.com%2Fquestions%2F119026%2Fquestion-on-sendmail-daemon-actions-when-load-average-is-too-high&data=user-a75bdc575572@xymon.invalid%7C5184c4e69cfc41d611ff08d5941f037d%7C47049324c4984be5acf70154448a1107%7C1%7C0%7C636577783282992025&sdata=gTT%2BrA7A88BosFDvteurJlcdKSi7XiT1ug6l%2FSd5zPg%3D&reserved=0>;


*From:* Xymon [mailto:xymon-bounces at xymon.com <xymon-bounces at xymon.com>] *On
Behalf Of *Root, Paul T
*Sent:* Tuesday, March 27, 2018 3:10 PM
*To:* 'Ajay Kumar Talla'; xymon at xymon.com
*Subject:* Re: [Xymon] Xymon - smtp


This is a load issue. Sendmail will refuse to process mail messages if the
CPU is too busy.


*From:* Xymon [mailto:xymon-bounces at xymon.com <xymon-bounces at xymon.com>] *On
Behalf Of *Ajay Kumar Talla
*Sent:* Tuesday, March 27, 2018 12:59 PM
*To:* xymon at xymon.com
*Subject:* [Xymon] Xymon - smtp


Hi,


I’m using smtp test in Xymon for monitoring. However sometimes, I’m
getting error as connection timed out.  After sometime it is showing as
Green(Flapping status)


Could you please, let me know the solution for this.


Thanks,

Ajay

This communication is the property of CenturyLink and may contain
confidential or privileged information. Unauthorized use of this
communication is strictly prohibited and may be unlawful. If you have
received this communication in error, please immediately notify the sender
by reply e-mail and destroy all copies of the communication and any
attachments.

This communication is the property of CenturyLink and may contain
confidential or privileged information. Unauthorized use of this
communication is strictly prohibited and may be unlawful. If you have
received this communication in error, please immediately notify the sender
by reply e-mail and destroy all copies of the communication and any
attachments.