#How to run dagger with podman (Fedora 42)

1 messages · Page 1 of 1 (latest)

olive swallow
#

Hello everyone. I am trying to run Dagger with Podman, but when I run the dagger command, it gets stuck at the connection stage.
I create podman machine with rotfull mode

 {
    "ConfigDir": {
       "Path": "/home/akiyamka/.config/containers/podman/machine/qemu"
    },
    "ConnectionInfo": {
       "PodmanSocket": {
            "Path": "/run/user/1000/podman/podman-machine-default-api.sock"
       },
       "PodmanPipe": null
    },
    "Created": "2025-12-02T21:42:08.841894053+01:00",
    "LastUp": "0001-01-01T00:00:00Z",
    "Name": "podman-machine-default",
    "Resources": {
       "CPUs": 8,
       "DiskSize": 100,
       "Memory": 2048,
       "USBs": []
    },
    "SSHConfig": {
       "IdentityPath": "/home/akiyamka/.local/share/containers/podman/machine/machine",
       "Port": 38589,
       "RemoteUsername": "core"
    },
    "State": "running",
    "UserModeNetworking": true,
    "Rootful": true,
    "Rosetta": false
 }

and enable sudo modprobe iptable_nat inside of it

But this not help, dagger steel can't connect to it

$ dagger
connect 1m
  starting engine ✓
  connecting to engine 1m
feral junco
olive swallow
feral junco
olive swallow
feral junco
olive swallow
#

this is more logs with

docker logs dagger-engine-v0.19.7 > log.log 2>&1
📎 log.log
olive swallow
feral junco
olive swallow
# feral junco sorry, this command: `docker run --rm -ti --privileged -v /var/lib/dagger regis... 
INFO[0000] detected mtu 65520 via interface wlp4s0
DEBU[2025-12-03T16:14:51Z] engine name: 6649c274e80a
DEBU[2025-12-03T16:14:51Z] creating engine GRPC server
DEBU[2025-12-03T16:14:51Z] creating engine lockfile
dnsmasq[43]: started, version 2.91 cachesize 150
dnsmasq[43]: compile time options: IPv6 GNU-getopt no-DBus no-UBus no-i18n no-IDN DHCP DHCPv6 no-Lua TFTP no-conntrack ipset no-nftset auth no-DNSSEC loop-detect inotify dumpfile
dnsmasq[43]: warning: interface dagger0 does not currently exist
dnsmasq[43]: using only locally-known addresses for dagger.local
dnsmasq[43]: reading /etc/dnsmasq-resolv.conf
dnsmasq[43]: using nameserver 169.254.1.1#53
dnsmasq[43]: using nameserver 100.100.100.100#53
dnsmasq[43]: using nameserver 192.168.100.1#53
dnsmasq[43]: using only locally-known addresses for dagger.local
DEBU[2025-12-03T16:14:51Z] creating engine server
dnsmasq[43]: read /etc/hosts - 19 names
dnsmasq[43]: read /var/run/containers/cni/dnsname/dagger/addnhosts - 0 names
INFO[2025-12-03T16:14:51Z] auto snapshotter: using overlayfs
DEBU[2025-12-03T16:14:51Z] could not read "/var/lib/dagger/net/cni" for cleanup: open /var/lib/dagger/net/cni: no such file or directory
dagger-engine: failed to create engine: failed to create network providers: CNI setup error: plugin type="bridge" failed (add): failed to list chains: running [/usr/local/sbin/iptables -t nat -S --wait]: exit status 3: iptables v1.8.11 (legacy): can't initialize iptables table `nat': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
feral junco
#

^ there's the error. seems like the iptable_nat module is not loaded in the machine kernel

#

does sudo lsmod | grep iptable_nat show anything?

olive swallow
feral junco
# olive swallow nothing

then the module is not loaded for some reason. Does sudo modprobe iptable_nat throw any error or anything?

olive swallow
#

I load it using sudo modprobe iptable_nat now it works

feral junco
#

👍

#

ok, maybe you rebooted the machine or something before and the module got unloaded

#

dagger should work now

olive swallow
#

now it instantly crash with

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0x55b8709f2c3f
olive swallow
feral junco
feral junco
feral junco
olive swallow
feral junco
olive swallow
# feral junco this one I mean

Sorry, i can't reproduce this again, I reboot system and now it works after I manually load iptable_nat. Seems like it not loaded by default in fedora

#

Thank you very much for your help. If I encounter a crash situation again, I will post the full trace here.

olive swallow
feral junco
# olive swallow It turns out that Fedora (starting from Fedora 33 (2020)) uses the `nftables` i...

No, not currently. This is becoming a bit of an issue as more distros transition to nftables . Skimming through the container plugins code, it seems like it should support nftables (https://github.com/containernetworking/plugins/blob/9b3772e1a7abf93cbb7c6526a28bc0d27b830e02/pkg/utils/netfilter.go#L41). Tagging @junior coyote and @spiral stump in case they have any pointers about this. Otherwise, we'd have to put some work in making it work 🙏

olive swallow