Using Transaction Signature (TSIG)¶
NSD supports Transaction Signature (TSIG) for zone transfer and for notify sending and receiving, for any query to the server.
TSIG keys are based on shared secrets. These must be configured in the config
file. To keep the secret in a separate file use
include: "filename" to
include that file.
An example TSIG key named
key: name: "sec1_key" algorithm: hmac-md5 secret: "6KM6qiKfwfEpamEq72HQdA=="
This key can then be used for any query to the NSD server. NSD will check if the signature is valid, and if so, return a signed answer. Unsigned queries will be given unsigned replies.
The key can be used to restrict the access control lists, for example to only allow zone transfer with the key, by listing the key name on the access control line.
# provides AXFR to the subnet when TSIG is used. provide-xfr: 10.11.12.0/24 sec1_key # allow only notifications that are signed allow-notify: 192.168.0.0/16 sec1_key
If the TSIG key name is used in
request-xfr lines, the key is
used to sign the request/notification messages.