Two network interfaces, only one (eth0) has an IPv4, why?

1 
incus network create web-network --type=bridge ipv4.address=10.10.10.1/24 ipv4.nat=true ipv6.address=none

incus network create sql-network --type=bridge ipv4.address=10.10.20.1/24 ipv4.nat=true ipv6.address=none

pastebin-container-profile.yaml :

```yaml
config: {}
description: profile for pastebin-container
devices:
  eth0:
    type: nic
    nictype: bridged
    parent: web-network
    ipv4.address: 10.10.10.3
  eth1:
    type: nic
    nictype: bridged
    parent: sql-network
    ipv4.address: 10.10.20.3
name: pastebin-container-profile
```

incus profile create pastebin-container-profile < pastebin-container-profile.yaml

incus launch images:debian/13 pastebin-container -p default -p pastebin-container-profile


incus exec pastebin-container -- ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host proto kernel_lo 
       valid_lft forever preferred_lft forever
33: eth0@if34: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 10:66:6a:e9:d0:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 10.10.10.3/24 metric 1024 brd 10.10.10.255 scope global dynamic eth0
       valid_lft 3588sec preferred_lft 3588sec
    inet6 fe80::1266:6aff:fee9:d002/64 scope link proto kernel_ll 
       valid_lft forever preferred_lft forever
35: eth1@if36: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 10:66:6a:54:8c:00 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::1266:6aff:fe54:8c00/64 scope link proto kernel_ll 
       valid_lft forever preferred_lft forever

the eth1 have not the IPv4 address, why ?
2

Most probable cause is that there is that eth1 is not defined in /etc/network/interfaces by default. If you want your container interfaces to be configured you have to use images:debian/13/cloud version of the images and use cloud-init.network-config configuration keys in your profile to setup interfaces with dhcp.