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Can only forward SSH from virtual network, but can't forward jellyfin or nginx. (lemmy.fish)

submitted 3 days ago* (last edited 3 days ago) by potentiallynotfelix@lemmy.fish to c/linux@lemmy.ml

6 comments fedilink hide all child comments

Here's an outline of the goal of my setup:

Guest VM 0(in NAT): 192.168.101.100:80 --> Host: 192.168.86.73:8080

Guest VM 1(in NAT): 192.168.101.85:8096 --> Host: 192.168.86.73:8081

Guest 1&0: 192.168.101.100:22 --> Host: 192.168.86.73:2222

I want to forward jellyfin from a vm to a host. Unfortunately, jellyfin doesn't let me do that. Everything is alma linux.

When going to 192.168.86.73:808(0,1) in a browser, I receive unable to connect, and when I wget it, I get Connecting to 192.168.86.73:8080... failed: No route to host.

However, I can ssh into the vms from ports 2222 and 2223. This is different from my last issue where I couldn't access any ports at all, ssh or web.

I set up a hook in /etc/libvirt/hooks/qemu according to this guide, which works for ssh but doesn't work for Jellyfin. I know jellyfin is working, because from my host machine I can run wget 192.168.101.100 and it returns the jellyfin home. I also know nginx isn't the issue for the same reason.

Here is my specific hook file:

#!/bin/bash

if [ "${1}" = "Jellyfin" ]; then

   # Update the following variables to fit your setup
   # Remember to change virbr0 to virbr1 if needed.
   GUEST_IP=192.168.101.100
   GUEST_PORT=22
   HOST_PORT=2222
   GUEST_PORT2=8096
   HOST_PORT2=8081

   if [ "${2}" = "stopped" ] || [ "${2}" = "reconnect" ]; then
    /sbin/iptables -D FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT -j ACCEPT
    /sbin/iptables -t nat -D PREROUTING -p tcp --dport $HOST_PORT -j DNAT --to $GUEST_IP:$GUEST_PORT
    /sbin/iptables -D FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT2 -j ACCEPT
    /sbin/iptables -t nat -D PREROUTING -p tcp --dport $HOST_PORT2 -j DNAT --to $GUEST_IP:$GUEST_PORT2
   fi
   if [ "${2}" = "start" ] || [ "${2}" = "reconnect" ]; then
    /sbin/iptables -I FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT -j ACCEPT
    /sbin/iptables -t nat -I PREROUTING -p tcp --dport $HOST_PORT -j DNAT --to $GUEST_IP:$GUEST_PORT
    /sbin/iptables -I FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT2 -j ACCEPT
    /sbin/iptables -t nat -I PREROUTING -p tcp --dport $HOST_PORT2 -j DNAT --to $GUEST_IP:$GUEST_PORT2
   fi
elif [ "${1}" = "Nginx" ]; then

   # Update the following variables to fit your setup
   # Remember to change virbr0 to virbr1 if needed.
   GUEST_IP=192.168.101.85
   GUEST_PORT=22
   HOST_PORT=2223
   GUEST_PORT2=80
   HOST_PORT2=8081

   if [ "${2}" = "stopped" ] || [ "${2}" = "reconnect" ]; then
    /sbin/iptables -D FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT -j ACCEPT
    /sbin/iptables -t nat -D PREROUTING -p tcp --dport $HOST_PORT -j DNAT --to $GUEST_IP:$GUEST_PORT
    /sbin/iptables -D FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT2 -j ACCEPT
    /sbin/iptables -t nat -D PREROUTING -p tcp --dport $HOST_PORT2 -j DNAT --to $GUEST_IP:$GUEST_PORT2
   fi
   if [ "${2}" = "start" ] || [ "${2}" = "reconnect" ]; then
    /sbin/iptables -I FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT -j ACCEPT
    /sbin/iptables -t nat -I PREROUTING -p tcp --dport $HOST_PORT -j DNAT --to $GUEST_IP:$GUEST_PORT
    /sbin/iptables -I FORWARD -o virbr1 -p tcp -d $GUEST_IP --dport $GUEST_PORT2 -j ACCEPT
    /sbin/iptables -t nat -I PREROUTING -p tcp --dport $HOST_PORT2 -j DNAT --to $GUEST_IP:$GUEST_PORT2
   fi
fi

Here is the result of iptables -nvL:

Chain INPUT (policy ACCEPT 82683 packets, 6162K bytes)
 pkts bytes target     prot opt in     out     source               destination         
82710 6165K LIBVIRT_INP  all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
   16   960 ACCEPT     tcp  --  *      virbr1  0.0.0.0/0            192.168.101.100      tcp dpt:8096
  153 13152 ACCEPT     tcp  --  *      virbr1  0.0.0.0/0            192.168.101.100      tcp dpt:22
  569  219K DOCKER-USER  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
  569  219K DOCKER-ISOLATION-STAGE-1  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0            ctstate RELATED,ESTABLISHED
    0     0 DOCKER     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  docker0 !docker0  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  docker0 docker0  0.0.0.0/0            0.0.0.0/0           
   44 32161 ACCEPT     all  --  *      br-8ac694360d19  0.0.0.0/0            0.0.0.0/0            ctstate RELATED,ESTABLISHED
    0     0 DOCKER     all  --  *      br-8ac694360d19  0.0.0.0/0            0.0.0.0/0           
   45  4419 ACCEPT     all  --  br-8ac694360d19 !br-8ac694360d19  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  br-8ac694360d19 br-8ac694360d19  0.0.0.0/0            0.0.0.0/0           
  480  183K LIBVIRT_FWX  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
  480  183K LIBVIRT_FWI  all  --  *      *       0.0.0.0/0            0.0.0.0/0           
  301 28065 LIBVIRT_FWO  all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain OUTPUT (policy ACCEPT 100K packets, 12M bytes)
 pkts bytes target     prot opt in     out     source               destination         
 100K   12M LIBVIRT_OUT  all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain DOCKER (2 references)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 ACCEPT     tcp  --  !br-8ac694360d19 br-8ac694360d19  0.0.0.0/0            172.18.0.5           tcp dpt:2283

Chain DOCKER-ISOLATION-STAGE-1 (1 references)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 DOCKER-ISOLATION-STAGE-2  all  --  docker0 !docker0  0.0.0.0/0            0.0.0.0/0           
   45  4419 DOCKER-ISOLATION-STAGE-2  all  --  br-8ac694360d19 !br-8ac694360d19  0.0.0.0/0            0.0.0.0/0           
  569  219K RETURN     all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain DOCKER-ISOLATION-STAGE-2 (2 references)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 DROP       all  --  *      docker0  0.0.0.0/0            0.0.0.0/0           
    0     0 DROP       all  --  *      br-8ac694360d19  0.0.0.0/0            0.0.0.0/0           
   45  4419 RETURN     all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain DOCKER-USER (1 references)
 pkts bytes target     prot opt in     out     source               destination         
  569  219K RETURN     all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain LIBVIRT_FWI (1 references)
 pkts bytes target     prot opt in     out     source               destination         
  179  154K ACCEPT     all  --  *      virbr1  0.0.0.0/0            192.168.101.0/24     ctstate RELATED,ESTABLISHED
    0     0 REJECT     all  --  *      virbr1  0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable
    0     0 ACCEPT     all  --  *      virbr0  0.0.0.0/0            192.168.122.0/24     ctstate RELATED,ESTABLISHED
    0     0 REJECT     all  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable

Chain LIBVIRT_FWO (1 references)
 pkts bytes target     prot opt in     out     source               destination         
  301 28065 ACCEPT     all  --  virbr1 *       192.168.101.0/24     0.0.0.0/0           
    0     0 REJECT     all  --  virbr1 *       0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable
    0     0 ACCEPT     all  --  virbr0 *       192.168.122.0/24     0.0.0.0/0           
    0     0 REJECT     all  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            reject-with icmp-port-unreachable

Chain LIBVIRT_FWX (1 references)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 ACCEPT     all  --  virbr1 virbr1  0.0.0.0/0            0.0.0.0/0           
    0     0 ACCEPT     all  --  virbr0 virbr0  0.0.0.0/0            0.0.0.0/0           

Chain LIBVIRT_INP (1 references)
 pkts bytes target     prot opt in     out     source               destination         
   24  2082 ACCEPT     udp  --  virbr1 *       0.0.0.0/0            0.0.0.0/0            udp dpt:53
    0     0 ACCEPT     tcp  --  virbr1 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:53
    3   966 ACCEPT     udp  --  virbr1 *       0.0.0.0/0            0.0.0.0/0            udp dpt:67
    0     0 ACCEPT     tcp  --  virbr1 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:67
    0     0 ACCEPT     udp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            udp dpt:53
    0     0 ACCEPT     tcp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:53
    0     0 ACCEPT     udp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            udp dpt:67
    0     0 ACCEPT     tcp  --  virbr0 *       0.0.0.0/0            0.0.0.0/0            tcp dpt:67

Chain LIBVIRT_OUT (1 references)
 pkts bytes target     prot opt in     out     source               destination         
    0     0 ACCEPT     udp  --  *      virbr1  0.0.0.0/0            0.0.0.0/0            udp dpt:53
    0     0 ACCEPT     tcp  --  *      virbr1  0.0.0.0/0            0.0.0.0/0            tcp dpt:53
    3   987 ACCEPT     udp  --  *      virbr1  0.0.0.0/0            0.0.0.0/0            udp dpt:68
    0     0 ACCEPT     tcp  --  *      virbr1  0.0.0.0/0            0.0.0.0/0            tcp dpt:68
    0     0 ACCEPT     udp  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            udp dpt:53
    0     0 ACCEPT     tcp  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            tcp dpt:53
    0     0 ACCEPT     udp  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            udp dpt:68
    0     0 ACCEPT     tcp  --  *      virbr0  0.0.0.0/0            0.0.0.0/0            tcp dpt:68

and iptables --list-rules

-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT
-N DOCKER
-N DOCKER-ISOLATION-STAGE-1
-N DOCKER-ISOLATION-STAGE-2
-N DOCKER-USER
-N LIBVIRT_FWI
-N LIBVIRT_FWO
-N LIBVIRT_FWX
-N LIBVIRT_INP
-N LIBVIRT_OUT
-A INPUT -j LIBVIRT_INP
-A FORWARD -d 192.168.101.100/32 -o virbr1 -p tcp -m tcp --dport 8096 -j ACCEPT
-A FORWARD -d 192.168.101.100/32 -o virbr1 -p tcp -m tcp --dport 22 -j ACCEPT
-A FORWARD -j DOCKER-USER
-A FORWARD -j DOCKER-ISOLATION-STAGE-1
-A FORWARD -o docker0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -o docker0 -j DOCKER
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
-A FORWARD -o br-8ac694360d19 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -o br-8ac694360d19 -j DOCKER
-A FORWARD -i br-8ac694360d19 ! -o br-8ac694360d19 -j ACCEPT
-A FORWARD -i br-8ac694360d19 -o br-8ac694360d19 -j ACCEPT
-A FORWARD -j LIBVIRT_FWX
-A FORWARD -j LIBVIRT_FWI
-A FORWARD -j LIBVIRT_FWO
-A OUTPUT -j LIBVIRT_OUT
-A DOCKER -d 172.18.0.5/32 ! -i br-8ac694360d19 -o br-8ac694360d19 -p tcp -m tcp --dport 2283 -j ACCEPT
-A DOCKER-ISOLATION-STAGE-1 -i docker0 ! -o docker0 -j DOCKER-ISOLATION-STAGE-2
-A DOCKER-ISOLATION-STAGE-1 -i br-8ac694360d19 ! -o br-8ac694360d19 -j DOCKER-ISOLATION-STAGE-2
-A DOCKER-ISOLATION-STAGE-1 -j RETURN
-A DOCKER-ISOLATION-STAGE-2 -o docker0 -j DROP
-A DOCKER-ISOLATION-STAGE-2 -o br-8ac694360d19 -j DROP
-A DOCKER-ISOLATION-STAGE-2 -j RETURN
-A DOCKER-USER -j RETURN
-A LIBVIRT_FWI -d 192.168.101.0/24 -o virbr1 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A LIBVIRT_FWI -o virbr1 -j REJECT --reject-with icmp-port-unreachable
-A LIBVIRT_FWI -d 192.168.122.0/24 -o virbr0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A LIBVIRT_FWI -o virbr0 -j REJECT --reject-with icmp-port-unreachable
-A LIBVIRT_FWO -s 192.168.101.0/24 -i virbr1 -j ACCEPT
-A LIBVIRT_FWO -i virbr1 -j REJECT --reject-with icmp-port-unreachable
-A LIBVIRT_FWO -s 192.168.122.0/24 -i virbr0 -j ACCEPT
-A LIBVIRT_FWO -i virbr0 -j REJECT --reject-with icmp-port-unreachable
-A LIBVIRT_FWX -i virbr1 -o virbr1 -j ACCEPT
-A LIBVIRT_FWX -i virbr0 -o virbr0 -j ACCEPT
-A LIBVIRT_INP -i virbr1 -p udp -m udp --dport 53 -j ACCEPT
-A LIBVIRT_INP -i virbr1 -p tcp -m tcp --dport 53 -j ACCEPT
-A LIBVIRT_INP -i virbr1 -p udp -m udp --dport 67 -j ACCEPT
-A LIBVIRT_INP -i virbr1 -p tcp -m tcp --dport 67 -j ACCEPT
-A LIBVIRT_INP -i virbr0 -p udp -m udp --dport 53 -j ACCEPT
-A LIBVIRT_INP -i virbr0 -p tcp -m tcp --dport 53 -j ACCEPT
-A LIBVIRT_INP -i virbr0 -p udp -m udp --dport 67 -j ACCEPT
-A LIBVIRT_INP -i virbr0 -p tcp -m tcp --dport 67 -j ACCEPT
-A LIBVIRT_OUT -o virbr1 -p udp -m udp --dport 53 -j ACCEPT
-A LIBVIRT_OUT -o virbr1 -p tcp -m tcp --dport 53 -j ACCEPT
-A LIBVIRT_OUT -o virbr1 -p udp -m udp --dport 68 -j ACCEPT
-A LIBVIRT_OUT -o virbr1 -p tcp -m tcp --dport 68 -j ACCEPT
-A LIBVIRT_OUT -o virbr0 -p udp -m udp --dport 53 -j ACCEPT
-A LIBVIRT_OUT -o virbr0 -p tcp -m tcp --dport 53 -j ACCEPT
-A LIBVIRT_OUT -o virbr0 -p udp -m udp --dport 68 -j ACCEPT
-A LIBVIRT_OUT -o virbr0 -p tcp -m tcp --dport 68 -j ACCEPT

Keep in mind I have docker running so some rules may not be relevant.

sysctl net.ipv4.ip_forward returns net.ipv4.ip_forward = 1

I've set the firewall backend of libvirt to iptables in /etc/libvirt/network.conf:

firewall_backend = "iptables"

Trying to solve this issue originally, I switched from Rocky to Fedora, but on my rocky and alma install this worked fine both times.

Thank you so much for the continued support with my issues!

top 6 comments

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[–] just_another_person@lemmy.world 4 points 3 days ago (1 children)

This is nearly impossible to decipher, but your problem is in the networking. You have two VMs with the same IPs, so fix that. You say "NAT", but I assume you're meaning a bridged network maybe? If you actually mean a NAT'd network, you're going above and beyond to really make this more difficult. I'd switch to something a bit more accessible.

[–] potentiallynotfelix@lemmy.fish 1 points 3 days ago (1 children)

Sorry! The ip was wrong, the nginx vm is 192.168.101.85. edited

[–] just_another_person@lemmy.world 4 points 3 days ago (1 children)

Well then your forwarding hook is broken and won't work for the second VM.

Just switch the networking type and make it easier on yourself. It seems you're following a guide or tutorial, and you're not familiar with what it's asking you to do.

Why are you even running these as VMs to begin with? I don't see that mentioned.

[–] potentiallynotfelix@lemmy.fish 1 points 3 days ago

Well then your forwarding hook is broken and won’t work for the second VM.

Because of the lack of clarity, I assume you meant something was wrong with the elif statement, so I ditched that.

    /sbin/iptables -t nat -I PREROUTING -p tcp --dport $HOST_PORT2 -j DNAT --to $GUEST_IP:$GUEST_PORT2
   fi
fi
if [ "${1}" = "Nginx" ]; then

My goal is to isolate Jellyfin and nginx from my seeing network. I'm not following any guide that wasn't linked in the post.

I want the VM so my system is more modular and secure.

[–] kork349d@lemmy.ml 1 points 3 days ago* (last edited 3 days ago) (1 children)

Have you considered macvtap? if you can work around the limitation of not accessing the guest directly from the host it will likely be an easier choice for setting up access to your jellyfinserver.

You did explain what they are trying to do but didn't explain why, which could help with suggestions on how to achieve what you are looking for in your setup.

[–] potentiallynotfelix@lemmy.fish 1 points 3 days ago

macvtap

This looks like some type of bridge mode, which I don't want. I want the vm to be isolated except for the jellyfin ports that are forwarded. I think nat mode and forwarding is the best if not only way to achieve this.