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awan_m's avatar
awan_m
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Jul 13, 2023

RESOLV::lookup not updating to new ip address

Hi -  My irule is usong the resolv statement to resolve a name -  set hostIP [lindex [RESOLV::lookup @$static::dns_vs inet -a $hostname] 0] we are experiencing issue when a DNS record is updated ...
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Paulius's avatar
Paulius
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awan_m Would you mind sharing the entire iRule that this resides in? Based on the information you have provided the DNS record should follow the TTL of the DNS record that was returned to it, so if your TTL for the record is lets say 5 hours then it could take up to 5 hours for the F5 to receive some other response.

awan_m's avatar
awan_m
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Jul 14, 2023

i understand the TTL part - but is there no way to clear cache and force a new resolution ?

  • Paulius's avatar
    Paulius
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    Jul 14, 2023

    awan_m You clear it the same way I believe you have been clearing it. I think the issue you are experiencing is that the cacheing NS still has the old record and not the new record and that is the issue you're running into. You should be able to double check this by logging into the CLI in bash and doing a "dig @<configured_dns_IP> <FQDN>" which will query the DNS server you have specified, which should be the same as the DNS server that the F5 has configured for DNS queries.