ACME dns challenge invalid with namecheap

chrwei

New Member
Apr 15, 2025
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I have the namecheap API access and whitelists setup. when I run the "order" I can see the TXT record created and then removed as it should be, but the result is just "invalid".

hitting the https://acme-v02.api.letsencrypt.org/acme/authz/xxx/yyy url after gives the error "DNS problem: NXDOMAIN looking up TXT for _acme-challenge.proxmox.<domainclipped> - check that a DNS record exists for this domain"

I do notice that running "dig _acme-challenge.proxmox.<domainclipped> TXT @dns1.registrar-servers.com", using the dns servers the domain registration shows to rule out any local dns caching, it takes about 40 seconds to give the TXT result, so I edited /usr/share/perl5/PVE/API2/ACME.pm to increase the 5 seconds to 20, but that did not change the result. I haven't been able to find where the "Sleeping 30 seconds to wait for TXT record propagation" message comes from, or a CLI option to extend it, but if I follow the logic it shouldn't matter as the 5->20 change should have the same effect.

I'm not sure where to go from here. I would like to use a private IP for this and not have my proxmox publicly accessible, but still be able to use a signed cert to access it.
 
I'm having the same issue. Were you ever able to resolve it? I logged into the namecheap portal and can see the new record show up and then get removed shortly after. This was working, I have a valid cert from 2025-01-08 through 2025-04-08 but then it just stopped working.

Loading ACME account details
Placing ACME order
Order URL: https://acme-v02.api.letsencrypt.org/acme/order/21584534534/426679345121

Getting authorization details from 'https://acme-v02.api.letsencrypt.org/acme/authz/2123479795/581234989211'
The validation for pts.mydomain.com is pending!
Add TXT record: _acme-challenge.pts.mydomain.com
Sleeping 30 seconds to wait for TXT record propagation
Triggering validation
Sleeping for 5 seconds
Remove TXT record: _acme-challenge.pts.mydomain.com
TASK ERROR: validating challenge 'https://acme-v02.api.letsencrypt.org/acme/authz/2587567375/581501234234121' failed - status: invalid, DNS problem: NXDOMAIN looking up TXT for _acme-challenge.pts.mydomain.com - check that a DNS record exists for this domain