Related to DDNS: ip not updated correctly

[Clara]

It seems that "./update_dns.sh" will add the new record correctly but do not remove the old one:

After changing "curl ifconfig.me" (this gave me an error) to "curl http://www.pkill.info/whoami/myip/" (as suggested in Eric's reply), I followed Amoner's instruction and `dig` worked correctly:

Code:

dig wretar.dthink.net @115.231.209.243
...
;; ANSWER SECTION:
wretar.dthink.net.    600    IN    A    119.63.98.21

But after I changed $ip in "update_dns.sh" and ran it again, `dig` gave me the following result:

Code:

;; ANSWER SECTION:
wretar.dthink.net.    600    IN    A    119.63.98.21
wretar.dthink.net.    600    IN    A    143.89.135.171

Maybe this is because that "update_dns.sh" only adds the new ip but does not remove the old one:

Code:

echo "update add $host 600 A $ip" >> dns_file