I can't explain the logging of those entries to my server. It filled my disk to 100% again this morning.

There is some existing report about the DNSQuestion logging part but I couldn't find any report about those SIP Asterisk entries. Nothing of that type is used on my side.

 
SEVERE: Could not find record type: dns[query,146.0.43.5:56100, length=426, id=0x4f50, flags=0x5449:aa, questions=1
questions:
        [DNSQuestion@323223758 type: TYPE_IGNORE index 0, class: CLASS_UNKNOWN index 0, name: 00@81.169.187.198 SIP/2.0
Via: SIP/2.0/UDP 146.0.43.5:56100;branch=z9hG4bK-1335804982;rport
Co.Length: 0
From: "asterisk"<sip:48413005736@1.7.0.0.1>;tag=3531613962626336313465390135373634323.303436
Accept: application/sdp
User-Agent: Asterisk.PBX 1.6.5
To: "asterisk"<sip:48.13005736@127.0.0.1>
Contact: sip:100@146.0.43.5:561.0
CSeq: 1 OPTIONS
Call-ID: 9716743636176791624.920
Max-Forwards: 70

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        question:      [DNSQuestion@323223758 type: TYPE_IGNORE index 0, class: CLASS_UNKNOWN index 0, name: 00@81.169.187.198 SIP/2.0
Via: SIP/2.0/UDP 146.0.43.5:56100;branch=z9hG4bK-1335804982;rport
Co.Length: 0
From: "asterisk"<sip:48413005736@1.7.0.0.1>;tag=3531613962626336313465390135373634323.303436
Accept: application/sdp
User-Agent: Asterisk.PBX 1.6.5
To: "asterisk"<sip:48.13005736@127.0.0.1>
Contact: sip:100@146.0.43.5:561.0
CSeq: 1 OPTIONS
Call-ID: 9716743636176791624.920
Max-Forwards: 70