You can use a blend of things, but these are the few that are most helpful.
First off we minimize the amount of traffic to services that cause the
service to hang up like NCSS. To "limit" the number of connections to NCSS
we use mod_limitipconn and reduce the number of connections per IP address
to the resource. So the NCSS urls only allow n number of connections per IP
address. Tuning the memory is key. TDS or tomcat or both act very oddly
when resources become scarce. Make sure you have a good handle on how you
are allocating memory in your tomcat settings... if you are using tomcat.
If you have NCML aggregations, upgrade to 4.5.x and start using
FeatureCollections. They do indexing ahead of time (similar to GDS) and it
finds the data much quicker and also reduces the amount of IO wait you add
to your server's load. There is a little more you need to do to migrate to
4.5.x, but it's worth the performance increase, especially with large
datasets.
Hope these suggestions help!
Phil
Phil Cogbill (Government Contractor)
Computer Programmer II, ERT, Inc.
National Integrated Drought Information System
National Climatic Data Center
Veach-Baley Federal Building
151 Patton Ave.
Room 355
Asheville, NC 28801-5001
Phil.Cogbill@xxxxxxxx
Desk: (828) 271-4474
Cell: (828) 419-0303
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On Thu, Aug 28, 2014 at 10:37 AM, tom cook <tmcook@xxxxxxxx> wrote:
> 4.2.8 :)
>
> On Thu, Aug 28, 2014 at 7:32 AM, Sean Arms <sarms@xxxxxxxx> wrote:
> > Hi Tim,
> >
> > Which version of the TDS are you using?
> >
> > Thanks!
> >
> > Sean
> >
> >
> > On Thu, Aug 28, 2014 at 8:21 AM, tom cook <tmcook@xxxxxxxx> wrote:
> >>
> >> Hi All,
> >> I'm hoping you can help me with a more sysadmin type issue. Over the
> >> past few days we have been unable to maintain a responsive TDS server
> >> for 24 hours. The remedy is to restart tomcat and then we are good to
> >> go. In the past, I've had issues with foreign IP addresses scanning
> >> directories and initiating large NCSS downloads, but I've blocked
> >> everything outside of the US. Looking through the logs, I'm seeing
> >> mostly US Govt affiliated connections, and some ISP/AmazonCloud
> >> servers. I kinda sorta know how to use netstat, but I'm having trouble
> >> id'ing the culprit or the culprits. Admittedly, the hardware is old
> >> (soon to be replaced), but I have a hunch this is related to NCSS,
> >> since that was always the service that brought us down in the past.
> >> So, I was wondering if any of you can help with suggestions/best
> >> practices/tips that you use to monitor and secure your incoming
> >> connections with TDS.
> >> Thanks,
> >> Tom
> >>
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> >
> >
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