Re: [EXTERNAL] Re: Need help on clamav database mirroring.

To my reading that page gives you all the answers to your questions.

cvdupdate grabs the cdiffs (and apparently daily.cvd etc) from the 
public CDN.

You then expose those downloaded files to your internal network however 
you find convenient, and configure freshclam on your internal clients to 
use the URL you've configured the files to be served from.

There is no "dns.txt" file;  there is a TXT record in DNS that declares 
the current signature definition versions.  cvdupdate and freshclam both 
use this by default to determine if an update is needed.

About halfway down that page:

====
Tip: If the freshclam clients will not have access to the internet to 
perform that DNS lookup, you may wish to set DNSDatabaseInfo no in your 
freshclam.conf file. freshclam may complain that the DNS lookup to "no" 
failed, which is fine. It will fall-back to checking the database 
version using an HTTP Range-request to your server.
====

-kgd



Khedkar, Atish via clamav-users wrote:
> Hello @Joel Esler <mailto:[email protected]>, I have gone through the 
> shared link before asking the question. I understood we can create 
> mirror repo using freshclam or cvdupdate. The freshclam sync only cvd 
> and cld files. However, I want use cvdupdate to sync cvd and cdiff 
> (patch) files. That’s why questions was around cvdupdate. As per the 
> documentation, I believe that cvdupdate does not allow to customize the 
> database URL and skip dns.txt file. Please let me know I had missed 
> anything.
> 
> Thanks,
> 
> Atish Khedkar
> 
> *From:*Joel Esler <[email protected]>
> *Sent:* Thursday, July 24, 2025 9:59 PM
> *To:* ClamAV users ML <[email protected]>
> *Cc:* Brendan Bell (brebell) <[email protected]>; Khedkar, Atish 
> <[email protected]>
> *Subject:* [EXTERNAL] Re: [clamav-users] Need help on clamav database 
> mirroring.
> 
> Atish —
> 
> Have you read Brendan’s link?
> 
> Hosting a Private Database Mirror - ClamAV Documentation 
> <https://urldefense.com/v3/__https:/docs.clamav.net/appendix/CvdPrivateMirror.html?highlight=setting*20DatabaseMirror*use-cvdupdate-to-serve-whole-databases-and-database-patch-files-from-a-private-mirror__;JSM!!PEZBYkTc!fv0qpaOkADJAc-XSube9I8s9-tS0ZsMzgoMDtLCgooRDg8qC2xpBeHWlV3RINMLaXW9244BlcWB_OAG0Jg$>
> 
> docs.clamav.net 
> <https://urldefense.com/v3/__https:/docs.clamav.net/appendix/CvdPrivateMirror.html?highlight=setting*20DatabaseMirror*use-cvdupdate-to-serve-whole-databases-and-database-patch-files-from-a-private-mirror__;JSM!!PEZBYkTc!fv0qpaOkADJAc-XSube9I8s9-tS0ZsMzgoMDtLCgooRDg8qC2xpBeHWlV3RINMLaXW9244BlcWB_OAG0Jg$>
> 
> 	
> 
> <https://urldefense.com/v3/__https:/docs.clamav.net/appendix/CvdPrivateMirror.html?highlight=setting*20DatabaseMirror*use-cvdupdate-to-serve-whole-databases-and-database-patch-files-from-a-private-mirror__;JSM!!PEZBYkTc!fv0qpaOkADJAc-XSube9I8s9-tS0ZsMzgoMDtLCgooRDg8qC2xpBeHWlV3RINMLaXW9244BlcWB_OAG0Jg$>
> 
> How to set up a private mirror is all documented there.
> 
> 
> 
>     On Jul 24, 2025, at 01:45, Khedkar, Atish via clamav-users
>     <[email protected]
>     <mailto:[email protected]>> wrote:
> 
>     Thanks@Brendan Bell (brebell) <mailto:[email protected]>for your help.
> 
>     I have understood the client side freshclam configuration. I had
>     questions regarding cvdupdate application.
> 
>      1. How to set custom target database URL instead
>         ofhttps://database.clamav.net
>         <https://urldefense.com/v3/__https:/database.clamav.net__;!!PEZBYkTc!aCVJ9EUumSmnWXgWa3QcXdEIj__rMfsN7kcesIJJ_gDXRLhFODaxn6-TbaJOSxW8qCUBc4qycw9D_vxB$>?
>      2. How to skip dns.txt download? We don’t want to host a DNS
>         database info server. It will be private database mirror repo.
> 
>     Thanks,
> 
>     Atish Khedkar
> 
>     *From:*Brendan Bell (brebell) <[email protected]
>     <mailto:[email protected]>>
>     *Sent:*Tuesday, July 22, 2025 10:37 PM
>     *To:*[email protected]
>     <mailto:[email protected]>
>     *Cc:*Khedkar, Atish <[email protected]
>     <mailto:[email protected]>>
>     *Subject:*[EXTERNAL] Re: Need help on clamav database mirroring.
> 
>     Hello Atish,
> 
>     Apologies for the delay.
> 
>     If I have correctly understood you question I believe you may want
>     to look into the following solutions.
> 
>      1.   Try setting DatabaseMirror in freshclam.conf to point at their
>         primary node. A little more detail can be found
>         here:https://docs.clamav.net/appendix/CvdPrivateMirror.html?highlight=setting%20DatabaseMirror#use-cvdupdate-to-serve-whole-databases-and-database-patch-files-from-a-private-mirror
>         <https://urldefense.com/v3/__https:/docs.clamav.net/appendix/CvdPrivateMirror.html?highlight=setting*20DatabaseMirror*use-cvdupdate-to-serve-whole-databases-and-database-patch-files-from-a-private-mirror__;JSM!!PEZBYkTc!aCVJ9EUumSmnWXgWa3QcXdEIj__rMfsN7kcesIJJ_gDXRLhFODaxn6-TbaJOSxW8qCUBc4qyc6N8Kf_N$>
> 
>     2.  We always recommend updating to the newest available version to
>     get the latest security fixes.  Currently 1.0.9 or 1.4.3 are the
>     recommended versions.  You can ignore dns.txt unless you are looking
>     to host a DNS database info server. As long as you keep your private
>     mirror updating at least every 24 hours you don't need to host a DNS
>     database server.
> 
>       There is nothing specific you need to do to support different
>     clamav client versions in your deployment. It is best to upgrade
>     older clients to ones supported versions in order to get the latest
>     security fixes. Right now these are 1.0.9 or 1.4.3. You can ignore
>     dns.txt unless you wish to host a DNS database info server. You
>     don't need to, so long as you keep your private mirror relatively up
>     to date (updating at least every 24 hours).
> 
>     ------------------------------------------------------------------------
> 
>     *From:* clamav-users <[email protected]
>     <mailto:[email protected]>> on behalf of
>     Khedkar, Atish via clamav-users <[email protected]
>     <mailto:[email protected]>>
>     *Sent:* Wednesday, July 16, 2025 11:48 AM
>     *To:* [email protected]
>     <mailto:[email protected]><[email protected]
>     <mailto:[email protected]>>
>     *Cc:* Khedkar, Atish <[email protected]
>     <mailto:[email protected]>>
>     *Subject:* [clamav-users] Need help on clamav database mirroring.
> 
>     Hello Team,
> 
>     There are multiple clamav (along with freshclam) nodes are deployed
>     in our Cloud Data Center. These clamav nodes are directly connecting
>     to public clamav database. That causes the connect rate limit on
>     this CDN as expected. The deployed clamav nodes can be on various
>     version (ranging from 0.104 to 1.4.0)
> 
>     As mentioned in clamav FAQ, we are setting up private mirror
>     repository as shown below in attached image. Following is our thought:
> 
>      1. Set up a*multi-pod ClamAV mirror repository* architecture with
>         a*primary/secondary model.*
> 
>          1. The primary node which runs cvd update every 6 hours and
>             stores .cvd, .cdiff, .cld, dns.txt etc.
>          2. The secondary node using cvd update should sync data from
>             primary node.
> 
>      2. Primary and Secondary nodes should maintain patches cdiff files
>         also.
> 
>     Based on above requirement, I have following question:
> 
>      1. How to set custom target database URL instead
>         ofhttps://database.clamav.net
>         <https://urldefense.com/v3/__https:/database.clamav.net__;!!PEZBYkTc!aCVJ9EUumSmnWXgWa3QcXdEIj__rMfsN7kcesIJJ_gDXRLhFODaxn6-TbaJOSxW8qCUBc4qycw9D_vxB$>?
>         In my case, how can I pass my primary repo URL?
>      2. If my client clamav version is ranging from 0.104 to 1.4.0 then
>         what thing I need to take care in mirror repository? Any thing
>         related to dns.txt?
> 
>     Thanks,
> 
>     Atish Khedkar
> 
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