Hi,
noticed this behavior:- XG configured for 3 DNS servers- on upstream device only those 3 DNS servers are allowed for XG- occasionally XG sends DNS request to many other DNS servers and these are denied by upstream device- issue on 18.5.1 and actual 18.5.2 too (observed that on prior versions too)- XG running as MTA and web proxy only
- when looking to such requests, that were PTR queries only
Not sure what triggers this behavior during operation.
I was able to replicate this behavior when cable was plugged out and then back in to the device.
Hi Tomas,
do you block you internal devices from sending DNS requests? I have some device and some applications that ignore the PC/MAC DNS settings, they do eventually fall back to the device DNS settings.
Ian
Xeon 1225v5 6gb ram, SSID, 4 NICs 20w - v19 EAP
XG115W - v18.5.2
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Check the logviewer, if you find the root cause of those connections. Who actually building up those connections.
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I do not know what is triggering it and haven't found anything specific. Today I started seeing the logs after I logged in to GUI to check logs. As I wrote above, even interface down/up can trigger that.Noticed too that sometimes it takes few hours of such logs, sometimes just minutes.To stop these logs I go in GUI to DNS page and 'apply' the settings again (no change at all).
As noted, it was just about PTR queries
Just review the IPs and seem the queries are for root servers. Some examples:192.203.230.10 e.root-servers.net128.63.2.53 h.root-servers.net199.7.83.42 l.root-servers.net
....