Bug 2417980

> On F41 ipv6 was rdy when httpd was started, on F42 it is NOT RDY in time.

If you have services binding to the IPv6 address, you need to set "[ipv6] may-fail=false" in the NM connection. This is documented in "man NetworkManager-wait-online" and "man nm-settings". There was no change in this regard from F41 to F42; perhaps it used to work only due to timing.

The old NetworkManager 1.50.x did not have this issue in general. Maybe some handling changed too? 

Nope.. NO CHANGE:

[ipv6]
addr-gen-mode=default
may-fail=false
address1=2a02.......
address2=2a02.......
method=manual

Dez 01 13:45:35 s129.resellerdesktop.de httpd[965]: (99)Cannot assign requested address: AH00072: make_sock: could not bind to address [2a02....]:80
Dez 01 13:45:35 s129.resellerdesktop.de httpd[965]: no listening sockets available, shutting down
Dez 01 13:45:35 s129.resellerdesktop.de httpd[965]: AH00015: Unable to open logs

       •   When a device reaches the activate state depends on its configuration. For example, with a profile that has both IPv4 and IPv6 enabled, by default, NetworkManager
           considers the device as fully activated already when only one of the address families is ready.

           The ipv4.may-fail and ipv6.may-fail settings control this behavior. Additionally, the following settings influence when the two address families complete:
           ipv4.required-timeout, ipv6.required-timeout, ipv4.dhcp-timeout, and ipv6.ra-timeout. For details, see nm-settings-nmcli(5).

Does the httpd service require "network-online.target" via "Want=" and orders after it with "After="? Is NetworkManager-wait-online.service enabled?

● NetworkManager-wait-online.service - Network Manager Wait Online
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager-wait-online.service; enabled; preset: enabled)
    Drop-In: /usr/lib/systemd/system/service.d
             └─10-timeout-abort.conf
     Active: active (exited) since Mon 2025-12-01 13:45:35 CET; 1h 42min ago

HTTPD:

I checked, its the normal httpd.service file, not an old one.

[Unit]
Description=The Apache HTTP Server
Wants=httpd-init.service
After=network.target remote-fs.target nss-lookup.target httpd-init.service
Documentation=man:httpd.service(8)
...
[Install]
WantedBy=multi-user.target

> After=network.target remote-fs.target nss-lookup.target httpd-init.service

There is no "After=network-online.target" ? Then httpd can start before NetworkManager has configured the addresses on the interface. See this from "man httpd.service":

   Starting the service at boot time
       The httpd.service and httpd.socket units are disabled by default. To start the
       httpd service at boot time, run: systemctl enable httpd.service. In the
       default configuration, the httpd daemon will accept connections on port 80
       (and, if mod_ssl is installed, TLS connections on port 443) for any configured
       IPv4 or IPv6 address.

       If httpd is configured to depend on any specific IP address (for example, with
       a "Listen" directive) which may only become available during start-up, or if
       httpd depends on other services (such as a database daemon), the service must
       be configured to ensure correct start-up ordering.

       For example, to ensure httpd is only running after all configured network
       interfaces are configured, create a drop-in file (as described above) with the
       following section:

           [Unit]
           After=network-online.target
           Wants=network-online.target

this does not explain, why ipv4 works, and ipv6 not. I will test it later, see if it helps.

btw: it does not make sense to start a webserver if there is no network to serve to. I suggest to add that dependency as a default, if they work.

(In reply to customercare from comment #6)
> this does not explain, why ipv4 works, and ipv6 not. I will test it later,
> see if it helps.

The difference could be that IPv4 addresses are configured immediately; for IPv6 addresses, kernel needs to perform DAD (duplicate address detection) before they can be used by httpd, which takes a couple of seconds.

> I suggest to add that dependency as a default, if they work.

If the HTTP server is not binding to a specific address, no dependency is needed. Anyway, if you think a dependency is missing in httpd, please reassign this ticket to a different component.

httpd fix seems to work..

I will switch the component to httpd, but i still think it's an NM >1.50.x issue, because it did not happen before the upgrade.

I added the suggested :

[Unit]
     After=network-online.target
     Wants=network-online.target


in this way :

[Unit]
Description=The Apache HTTP Server (prefork MPM)
After=syslog.target network.target remote-fs.target nss-lookup.target network-online.target
Wants=network-online.target

As we have custom services files for apache.

This is expected and documented exactly as Beniamino explains in comment 5 and comment 8.