Excessive DNS queries to download.qnap.com

[eggic]

Hello all,

I recently reconfigured my network to use pi.hole for ad blocking and local DNS management and noted my QNAP 870 Pro queries download.qnap.com once a minute 24hrs/day 7 days a week. Is this normal and if so is there a way to change the frequency?

My configuration is:

Host: TS 870 Pro with 5 x WD RED 4TB disks (RAID6) + 1 x 128 GB SSD
Firmware: 4.2.1 Build 20161214
Enabled Apps: CloudLink, myQNAPCloud SSL Certificate, Network & Virtual Switch, CodexPack, Plex Media Server, Entware-ng

Thanks!

[dolbyman]

online checks for the NAS

[OneCD]

Is it causing a problem?

[keen4listerine]

I would consider this more of a problem than an annoyance. The problem is that the QNAP requests blows out your pihole log file. When attempting to grab any sort of data from the web admin page it tops out the CPU for the pi-hole. Makes it hard to troubleshoot if you don't know your way around a terminal.

I'd much prefer to have the option to control my QNAP on how often it performs these checks. Multiple checks every minute is quite excessive.

[Shade00]

I too am experiencing this issue. Hits to download.qnap.com make up easily 3 times the next domain on my pihole. Please, please, Qnap, let us stop this.

[OneCD]

blows out your pihole

I think that's my new favorite expression.

From the logs that have been listed, it seems that both IPv4 and IPv6 requests are made each minute.

It wouldn't be too hard to write an iptables rule to block this - maybe with periodic unblocking.

So, I guess the question then becomes: what would the average pi-hole user consider to be an acceptable ping frequency?

[P3R]

I'd much prefer to have the option to control my QNAP on how often it performs these checks.

1. It may appear excessive to a user but there is nothing wrong with what Qnap do.
2. The feature request proposed here wouldn't really improve the Qnap product, it would only solve an unwanted consequence in a third party software.
3. Implementing this as a admin gui tunable feature would increase development and support cost for Qnap.
4. Implementing this as a admin gui tunable feature would confuse non-educated users and make their Qnap experience less intuitive.
5. This is a problem for very, very, very few Qnap users.

Given the above, I don't think this feature request will ever be implemented. Therefore I would instead recommend some workaround (maybe the one OneCD think about?) to be manually implemented by the very, very, very few users that think this is an annoyance/problem.

Anyway, if you still want to get attention from Qnap for the feature request, this forum is the wrong place. Instead please contact Qnap support, open a ticket and file your feature request there. Then it will at least be seen by Qnap.

[OneCD]

I'd much prefer to have the option to control my QNAP on how often it performs these checks.

2. The feature request proposed here wouldn't really improve the Qnap product, it would only solve an unwanted consequence in a third party software.

That's true, and it should also be noted that implementing a block may have a detrimental effect on the originating software.

[JillyPolla]

How is this a problem with third party software, and how is this problem only a very very small number of QNAP users have? Pretty much every QNAP user have this problem of excessive pinging of download.qnap.com if you're on QNAP firmware (which is first party software).

The only work-around I have for this issue is to set the dns server inside the adapter setting in your QNAP web console so that DNS requests are sent directly to an external DNS (like Google's 8.8.8. instead of flooding your router or pi-hole.

[dolbyman]

pings once per minute will not flood even the most underpowered router

[P3R]

How is this a problem with third party software, and how is this problem only a very very small number of QNAP users have? Pretty much every QNAP user have this problem of excessive pinging of download.qnap.com if you're on QNAP firmware (which is first party software).

Qnap seems to be using these DNS queries as one of their connectivity testing strategies and there may be a number of reasons unknown to you and me for the frequency selected by Qnap. DNS queries or even "excessive" (whatever that is?) DNS queries isn't a problem to 99.99 % of Qnap users as it isn't noticed unless specifically sniffing for it.

The few that (so far) are seeing any ill-effects (flooded logs) of this behaviour are users of the the third party pi.hole thing.

The logical thing for me to do would be to ask for log filtering capability in pi.hole. That would be useful to many more people as that could solve other issues as well for the whole pi.hole user base.

The only work-around I have for this issue is to set the dns server inside the adapter setting in your QNAP web console so that DNS requests are sent directly to an external DNS (like Google's 8.8.8. instead of flooding your router or pi-hole.

See, you fixed the "problem" yourself already with a simple configuration change. Real problems aren't fixed that easy...

[xSunshin3x]

a nas should not be contacting qnap servers every single minute of the day.

+1 on that.

The NAS belongs to me and shouldn't contact the vendor if not necessary.


I experienced the same "issue" in my dns server log.

Login via ssh with admin credentials and a quick look into cron with 'crontab -e' reveals 2 script running periodically every minute.
Since i didn't want to mess around with the internal structure of the QNAP filesystem, i found out that there is a option called "System Default Gateway".

You can find this in the web-gui of your NAS, Control Panel -> Network & File Services -> Network & Virtual Switch -> System Default Gateway.

There you have to manually select the system default gateway (instead of "The system will automatically detect" (this is the default option on the NAS and seems to produce the dns queries))

After changing this option, the QNAP NAS stopped sending any periodically DNS queries to the (in my case) local dns server.


Hope this helps for you as well (:

[keen4listerine]

Made the changes as xSunshin3x suggested. Confirmed all is good. Thanks

[xSunshin3x]

It's me again, back with the same ol' problem :/

edit: never mind, seems to be back after a reboot/firmware upgrade. did both, not sure what reset it.

Can confirm. One of both events triggered it - i assume it was the firmware upgrade, since the excessive dns queries also started on my nas after updating to 4.3.3.0188 Build 20170516.
I did another firmware update (including a restart of the nas) in between my first post and the latest firmware update and i'm pretty sure the nas didn't send any periodically queries after the first update.

Can you confirm that you're on Build 20170516 as well?`

i tried to disable the two scripts i mentioned earlier (uncomment in crontab) but it gets resetted after a reboot.

Haven't figured out another workaround yet. Thinking about blacklisting download.qnap.com but im not exactly sure about the aftermath (maybe firmware check/download will not be possible then) + this would only be a quick and dirty workaround and not solving the initial problem/cause at all..


But it's nice to read that i'm not the only one disappointed about QNAPs 'policy' of not allowing the user to do what he wants with his property (e.g. uninstalling the QTS SSL Certificate app is disabled by default and can only be enabled via ssh)

[Don]

Want QNAP to do something then open a ticket. They rarely follow the forum.