Hey all, For the last 8 months I have been running a postfix / mail scanner setup based on Johnny Hughes' excellent tutorial. For the firs 7 months I have had no issues. This past month I have been having instances where the user gets an smtp error while trying to send email. Restarting the postfix service is all it takes to resolve this issue. The problem is that it has begun to occur more and more often. It is now up to once every day. I have found nothing unusual in the mail or messages logs. As I am an ultra newbie I am unsure of the next step to take to resolve this. I have search through the past messages on this list and can find nothing. Anyone have any ideas? Thanks, Jason Ross
Jason Ross spake the following on 8/9/2007 1:39 PM:> Hey all, > > For the last 8 months I have been running a postfix / mail scanner setup > based on Johnny Hughes' excellent tutorial. > For the firs 7 months I have had no issues. This past month I have been > having instances where the user gets an smtp error while trying to send > email. > Restarting the postfix service is all it takes to resolve this issue. > The problem is that it has begun to occur more and more often. It is now > up to once every day. > I have found nothing unusual in the mail or messages logs. As I am an > ultra newbie I am unsure of the next step to take to resolve this. > I have search through the past messages on this list and can find > nothing. Anyone have any ideas? > > Thanks, > > Jason RossHave you done any normal maintenance such as OS upgrades? Software fixes? Did you do one about a month ago? -- MailScanner is like deodorant... You hope everybody uses it, and you notice quickly if they don't!!!!
Jason Ross wrote:> Hey all, > > For the last 8 months I have been running a postfix / mail scanner setup > based on Johnny Hughes' excellent tutorial. > For the firs 7 months I have had no issues. This past month I have been > having instances where the user gets an smtp error while trying to send > email. > Restarting the postfix service is all it takes to resolve this issue. > The problem is that it has begun to occur more and more often. It is now > up to once every day. > I have found nothing unusual in the mail or messages logs. As I am an > ultra newbie I am unsure of the next step to take to resolve this. > I have search through the past messages on this list and can find > nothing. Anyone have any ideas?The following details would be nice: Number of smtpd daemons configured (if you have not changed then it is 100), number of smtpds, cleanups and trivial-rewrites running when you encounter the problem, cpu utilization statistics. I am not familiar with how mail-scanner is run. I assume it has a fixed number of processes. Are all mail-scanner processes in action during the smtp timeout and taking the majority of cpu resources?
On 09 August 2007, Ken Price <kprice at nowyouknow.net> wrote: <snip>> I'll give my two cents and retire for the evening. I've tried > multiple times from 3 different locations (Atlanta & Seattle) to > connect to MAIL.MEDVOICE.COM on port 25 ... which I'm assuming is your > problem server. I get inconsistent results. Half the time I get a > near immediate (<2 seconds) 220 prompt. The rest of the time I get > > 10 seconds or timeouts. >I tried his SMTP this morning and it was either OK or timeout.> 3) Who does your DNS? Looks like Qwest is authoritative for your > domain, do you use their recursive DNS servers too? If yes, this > could be a problem. If you don't already, RUN YOUR OWN RECURSIVE DNS > for your server!! > Bandwidth and DNS are the likely culprits.Possibly someone who knows a *lot* more about DNS management than I do can look at his DNS management? I have the ttl (IN) for "A" and "PTR" at 3600s for my web site. Faster, if one changes IP address. He has those ttl at 100000s. Possibly he could use the IP address more, in DNS management? I've had the SMTP service die, over the past 68 months, approximately 10-15 times, on a RH server (shared hosting). Never daily. Services and processes sometimes die mysteriously, but probably not on a daily basis. In the WHOIS record:> Name Server: AUTHNS3.STTL.QWEST.NET > Name Server: AUTHNS1.MPLS.QWEST.NET > Name Server: AUTHNS2.DNVR.QWEST.NETPossibly those should be in different order? (I have mine, NS1, NS2, NS3, NS4 from top to bottom)
Rick, The reason i used top was because I noticed that mailscanner and smtpd were always on the list UNLESS the issue was occurring. I will try ps + grep next time as well. As for the ips they resolve quickly however they are all listed in /etc/hosts as we do not have an internal DNS. -jr replies-lists-a1z2-centos at listmail.innovate.net wrote:> using "top" to look for processes probably isn't the best approach as > (by default) you'll only see the more resource intensive applications. > you'll probably get a better picture of things related to a specific > application using "ps" (and grep). > > when you connect to an MTA (e.g., postfix/sendmail) it will try to do > an reverse map lookup on the ipnumber of the inbound connection. if you > don't have in-addr.apra entries for your ipnumbers, or if the machine > running your MTA is having trouble getting to the dns server for the > ipnumber range, then you'll get the type of delays you seem to be > seeing. ultimately the dns will time out (the number of dns servers you > have listed in your mail server's /etc/resolv.conf will effect this - > more is not better). > > you can get a sense of whether this is the issue by doing lookups (on > the mail server) of the ipnumber(s) for connecting machines that are > encountering the delay. depending on your configuration, your server > may cache a result, so the first may be slow with subsequent ones > being fast (until you hit the TTL on the record). > > [by the way, when sending to a mailing list please try to suppress your > confidentiality notice as it's meaningless in this context, and takes > up a lot of lines.] > > - Rick > >