Error connect tunnel with KubeVPN when IPv6 disable.

[leduyquy]

Hello.

I have setup KubeVPN for my cluster but when use kubectl connect to cluster with kubevpn plugin it show error can not setup ipv6. For my company policy, we must disable IPv6 on our computers and not enable it.

Is there any way we can setup a tunnel with kubevpn without enabling IPv6 on my PC?

Thank you.

[wencaiwulue]

：> Hello.

I have setup KubeVPN for my cluster but when use kubectl connect to cluster with kubevpn plugin it show error can not setup ipv6. For my company policy, we must disable IPv6 on our computers and not enable it.

Is there any way we can setup a tunnel with kubevpn without enabling IPv6 on my PC?

Thank you.

@leduyquy can you provide some log, and which os you are using? macos/windows/linux

[leduyquy]

Hi @whomobile

This is out put log when I connect with IPv6 disable.

I'm using Ubuntu 23.10

[wencaiwulue]

Hi @whomobile

This is out put log when I connect with IPv6 disable.

I'm using Ubuntu 23.10

got it, by the way. I am @wencaiwulue ...

[wencaiwulue]

@leduyquy can you use the following code, and save to main.go, then run it with ·go run main.go·, and show the result? i want to detect if ipv6 is enabled ~ thanks in advance ~

package main

import (
    "fmt"
    "net"
    "os"
)

func main() {
    addrs, err := net.InterfaceAddrs()
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    ipv6Enabled := false
    for _, addr := range addrs {
        // Type assertion to net.IPNet to get the IP address without the mask.
        if ipNet, ok := addr.(*net.IPNet); ok && ipNet.IP.To16() != nil {
            if ipNet.IP.To4() == nil { // This is an IPv6 address
                ipv6Enabled = true
                break
            }
        }
    }

    if ipv6Enabled {
        fmt.Println("IPv6 is enabled on this system.")
    } else {
        fmt.Println("IPv6 is not enabled on this system.")
    }
}

[leduyquy]

Hi @wencaiwulue

This is result

[wencaiwulue]

Hi @wencaiwulue

This is result

ok, got it, i will use this way to detect ipv6 is enable or not. thanks

[whomobile]

Hi @wencaiwulue

kubevpn/pkg/tun/tun_bsd.go

Line 58 in 984ab2c

ipv4, _, err = net.ParseCIDR(cfg.Addr6)

cfg.Addr instead of Addr6 ?

quick search https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20net.ParseCIDR&type=code
show other platform use Addr

but it looks not root cause.
https://github.com/kubenetworks/kubevpn/blob/984ab2ce89d925352aeff79cbfda3fb89cf7d834/pkg/tun/tun_bsd.go#L62C3-L62C82

[wencaiwulue]

Hi @wencaiwulue

kubevpn/pkg/tun/tun_bsd.go

Line 58 in 984ab2c

ipv4, _, err = net.ParseCIDR(cfg.Addr6)

cfg.Addr instead of Addr6 ?

quick search https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20net.ParseCIDR&type=code show other platform use Addr

but it looks not root cause. https://github.com/kubenetworks/kubevpn/blob/984ab2ce89d925352aeff79cbfda3fb89cf7d834/pkg/tun/tun_bsd.go#L62C3-L62C82

Yes, bug 😂, maybe nobody using kubevpn on bsd system 😂😂😂

[wencaiwulue]

@leduyquy commit: #248 can you pull this branch code, and make kubevpn manually? github attachment max size is 50Mb😂

[wencaiwulue]

Hi @whomobile

kubevpn/pkg/tun/tun_bsd.go

Line 58 in 984ab2c

ipv4, _, err = net.ParseCIDR(cfg.Addr6)

cfg.Addr instead of Addr6 ?

quick search https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20net.ParseCIDR&type=code show other platform use Addr

but it looks not root cause. https://github.com/kubenetworks/kubevpn/blob/984ab2ce89d925352aeff79cbfda3fb89cf7d834/pkg/tun/tun_bsd.go#L62C3-L62C82

here is commit: #249, please take a review, thanks ~

[whomobile]

maybe better check if ipv6 enabled from below.

kubevpn/pkg/core/route.go

Line 88 in cc032c4

Addr6: os.Getenv(config.EnvInboundPodTunIPv6),

also based on below. how come even that env var set the value if IPv6 is not enabled?
https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20EnvInboundPodTunIPv6&type=code

It looks like below can be issue when IPv6 is not enabled.

kubevpn/pkg/config/config.go

Line 56 in cc032c4

innerIPv6Pool = "efff:ffff:ffff:ffff:ffff:ffff:ffff:9999/64"

[leduyquy]

@leduyquy commit: #248 can you pull this branch code, and make kubevpn manually? github attachment max size is 50Mb😂

I testing with this branch it working, many thanks.

[wencaiwulue]

maybe better check if ipv6 enabled from below.

kubevpn/pkg/core/route.go

Line 88 in cc032c4

Addr6: os.Getenv(config.EnvInboundPodTunIPv6),

also based on below. how come even that env var set the value if IPv6 is not enabled? https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20EnvInboundPodTunIPv6&type=code

It looks like below can be issue when IPv6 is not enabled.

kubevpn/pkg/config/config.go

Line 56 in cc032c4

innerIPv6Pool = "efff:ffff:ffff:ffff:ffff:ffff:ffff:9999/64"

Yes, you are right. If env ipv6 set, means wants to set ipv6 addr. Maybe better way is add flag --stack v4/v6/both/auto. when we connect to cluster. We can special this option. Set env var more early. Not so late when use it then to check.

[wencaiwulue]

maybe better check if ipv6 enabled from below.

kubevpn/pkg/core/route.go

Line 88 in cc032c4

Addr6: os.Getenv(config.EnvInboundPodTunIPv6),

also based on below. how come even that env var set the value if IPv6 is not enabled? https://github.com/search?q=repo%3Akubenetworks%2Fkubevpn%20EnvInboundPodTunIPv6&type=code

It looks like below can be issue when IPv6 is not enabled.

kubevpn/pkg/config/config.go

Line 56 in cc032c4

innerIPv6Pool = "efff:ffff:ffff:ffff:ffff:ffff:ffff:9999/64"

@whomobile
I make some change: 14e421c

[wencaiwulue]

@leduyquy already release v2.2.9, you can have a try ~