DNS

16 BADVERS/BADSIG

Bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.

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When You See This Code

As BADVERS: your client sent an EDNS version higher than the server supports. As BADSIG: the TSIG MAC on the message did not match, indicating a shared-secret mismatch or message tampering.

How to Fix

For BADVERS, downgrade the EDNS version (most servers support version 0 only). For BADSIG, regenerate and re-synchronize the TSIG shared secret on both endpoints.

Specification

View RFC / Specification →

Compare With

0 NOERROR 1 FORMERR 2 SERVFAIL 3 NXDOMAIN 4 NOTIMP 5 REFUSED 6 YXDOMAIN 7 YXRRSET 8 NXRRSET 9 NOTAUTH 10 NOTZONE 11 DSOTYPENI

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Frequently Asked Questions

What is DNS 16 BADVERS/BADSIG?

Bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.

When do you see DNS 16 BADVERS/BADSIG?

As BADVERS: your client sent an EDNS version higher than the server supports. As BADSIG: the TSIG MAC on the message did not match, indicating a shared-secret mismatch or message tampering.

How to fix DNS 16 BADVERS/BADSIG?

For BADVERS, downgrade the EDNS version (most servers support version 0 only). For BADSIG, regenerate and re-synchronize the TSIG shared secret on both endpoints.