gre routing, debian 11 virtfusion. I'll pay for help if needed.

nszerver

error, putty not connected.
I'll pay for help if needed.

//////////////////////////interface///////////////

This file describes the network interfaces available on your system

and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

The loopback network interface

auto lo
iface lo inet loopback

The primary network interface

allow-hotplug enp4s0
iface enp4s0 inet static
address xxx.115.109.66/29
gateway xxx.115.109.65
# dns-* options are implemented by the resolvconf package, if installed
dns-nameservers 127.0.0.1
dns-search 46459

iface vmbr2 inet static
address xx5.xxx.228.64/29
netmask 255.255.255.248
bridge_ports none
bridge_stp none
bridge_fd 0
dns-nameservers 8.8.8.8
up ip link set dev gre1 up
pre-up /root/gre.sh
pre-up ip link add name gre1 type gretap local xxx.115.109.66 remote 5.230.>
pre-up ip addr add 10.0.1.2/30 dev gre1
pre-up ip route add default via 10.0.1.1 dev gre1
post-up ip link set vmbr2 mtu 1462
post-down ip link set dev gre1 down
post-down ip link del gre1

////////////////////////gre.sh//////////////////////////

!/bin/sh

ip tunnel add gre1 mode gre local xxx.115.109.66 remote 5.230.205.35 ttl 255
ip addr add 10.0.1.2/30 dev gre1
ip link set gre1 up
ip route add xx5.xxx.228.64/29 dev vmbr2
ip route add xx5.xxx.228.65/32 dev vmbr2
ip route add xx5.xxx.228.66/32 dev vmbr2
ip route add xx5.xxx.228.67/32 dev vmbr2
ip route add xx5.xxx.228.68/32 dev vmbr2
ip route add xx5.xxx.228.69/32 dev vmbr2
ip route add xx5.xxx.228.70/32 dev vmbr2
ip route add xx5.xxx.228.71/32 dev vmbr2
ip route add default via 10.0.1.1 dev gre1 table 20
sudo brctl addif vmbr2 gre1

///////////////////////ifconfig list//////////////////////////////////
640322027: flags=4099<UP,BROADCAST,MULTICAST> mtu 1462
ether 00:69:76:63:d9:72 txqueuelen 500 (Ethernet)
RX packets 0 bytes 0 (0.0
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

enp4s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet xxx.115.109.66 netmask 255.255.255.248 broadcast 0.0.0.0
inet6 fe80::230:48ff:fed3:8664 prefixlen 64 scopeid 0x20
ether 00:30:48:d3:86:64 txqueuelen 1000 (Ethernet)
RX packets 25941 bytes 2119855 (2.0 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 5736 bytes 3766048 (3.5 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device interrupt 16 memory 0xfc100000-fc120000

gre1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1462
inet 10.0.1.2 netmask 255.255.255.252 broadcast 0.0.0.0
inet6 fe80::3cde:2eff:fe00:205a prefixlen 64 scopeid 0x20
ether 3e:de:2e:00:20:5a txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 9 bytes 544 (544.0
TX errors 3 dropped 0 overruns 0 carrier 3 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10
loop txqueuelen 1000 (Local Loopback)
RX packets 48093 bytes 17967349 (17.1 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 48093 bytes 17967349 (17.1 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

vmbr2: flags=4099<UP,BROADCAST,MULTICAST> mtu 1462
inet xx5.xxx.228.64 netmask 255.255.255.248 broadcast 0.0.0.0
inet6 fe80::7072:3cff:fe22:7093 prefixlen 64 scopeid 0x20
ether 72:72:3c:22:70:93 txqueuelen 1000 (Ethernet)
RX packets 75 bytes 3796 (3.7 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 20 bytes 2100 (2.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

////////////////////////////////ip route show////////////////////////////
default via xxx.115.109.65 dev enp4s0 proto kernel onlink
xx5.xxx.228.64/29 dev vmbr2 proto kernel scope link src xx5.xxx.228.64 linkdown
10.0.1.0/30 dev gre1 proto kernel scope link src 10.0.1.2
xxx.115.109.64/29 dev enp4s0 proto kernel scope link src xxx.115.109.66
///////////////////////ip a /////////////////////////////////////////
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
valid_lft forever preferred_lft forever
2: enp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:30:48:d3:86:64 brd ff:ff:ff:ff:ff:ff
inet xxx.115.109.66/29 scope global enp4s0
valid_lft forever preferred_lft forever
inet6 fe80::230:48ff:fed3:8664/64 scope link
valid_lft forever preferred_lft forever
3: enp5s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 00:30:48:d3:86:65 brd ff:ff:ff:ff:ff:ff
4: gre0@NONE: mtu 1476 qdisc noop state DOWN group default qlen 1000
link/gre 0.0.0.0 brd 0.0.0.0
5: gretap0@NONE: <BROADCAST,MULTICAST> mtu 1462 qdisc noop state DOWN group default qlen 1000
link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
6: erspan0@NONE: <BROADCAST,MULTICAST> mtu 1450 qdisc noop state DOWN group default qlen 1000
link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
10: gre1@NONE: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1462 qdisc pfifo_fast state UNKNOWN group default qlen 1000
link/ether 3e:de:2e:00:20:5a brd ff:ff:ff:ff:ff:ff
inet 10.0.1.2/30 scope global gre1
valid_lft forever preferred_lft forever
inet6 fe80::3cde:2eff:fe00:205a/64 scope link
valid_lft forever preferred_lft forever
11: vmbr2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1462 qdisc noqueue state UP group default qlen 1000
link/ether 72:72:3c:22:70:93 brd ff:ff:ff:ff:ff:ff
inet xx5.xxx.228.64/29 scope global vmbr2
valid_lft forever preferred_lft forever
inet6 fe80::7072:3cff:fe22:7093/64 scope link
valid_lft forever preferred_lft forever
13: 3640322027: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1462 qdisc noqueue master vmbr2 state UNKNOWN group default qlen 1000
link/ether fe:69:76:63:d9:72 brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc69:76ff:fe63:d972/64 scope link
valid_lft forever preferred_lft forever

/////////////////////virtfusion/////////////////////////////
kvm birdged:
netmask: 255.255.255.248
gateway: xx5.xxx.228.64
dns: 8.8.8.8 8.8.4.4

ip address: xx5.xxx.228.65-70
////////////////////////////////vps ip ///////////////////////////////
ip address: xx5.xxx.228.66

Erro vps ssh, network error connection time out.
I'll pay for help if needed.
Thank you very much, there is internet in the vps, you can connect to it from a server, but unfortunately not on an external network, you can reach it.

anubhavhirani

Good

anubhavhirani

IDK what is going on here, is passwordAuthentication set to Yes ?

Andreix

The configuration and command output snippets you've provided suggest a complex networking setup on a Linux host, involving GRE tunnels, bridged interfaces, and static IP configurations. It appears you are having trouble connecting to your Virtual Private Server (VPS) via SSH, evidenced by a "network error connection time out" message. The problem could be arising from a multitude of factors including incorrect configuration, network issues, or firewall rules. Here are some steps and considerations to help you troubleshoot the issue:

1. Check IP Configuration:

   • Ensure that the IP addresses, subnet masks, and gateway configurations in /etc/network/interfaces, gre.sh, and your virtualization setup (KVM) are correct and coherent.
   • The configured DNS servers should be reachable. You can test this using the ping or dig command.
   • The routing table (ip route show output) should have correct entries for reaching the VPS IP and other networks.

2. Check Network Connectivity:

   • From the host machine, try pinging the VPS IP (xx5.xxx.228.66) and the gateway (xx5.xxx.228.64). If these pings fail, there might be a network connectivity issue.
   • Check if there are any firewall rules blocking the SSH traffic on port 22. You can use iptables -L or ufw status to check the firewall rules.
   • Check the MTU values. The MTU on gre1 and vmbr2 is set to 1462, while enp4s0 is set to 1500. MTU mismatches can cause packet fragmentation or dropping.

3. Check SSH Service:

   • Ensure that the SSH service is running on the VPS. If possible, access the VPS console via your virtualization management interface and run systemctl status sshd.
   • Check the SSH configuration file (/etc/ssh/sshd_config) on the VPS for any restrictive settings like AllowUsers, AllowGroups, or ListenAddress.

4. Check Virtualization Networking:

   • Verify the networking configuration within your virtualization setup (KVM). Ensure that the network bridge vmbr2 is correctly set up and that the VPS is attached to the correct network.
   • The network configuration for KVM should align with the settings in /etc/network/interfaces and gre.sh.

5. Check System Logs:

   • Check the system logs on the host and the VPS for any networking or SSH-related errors. You can use dmesg, journalctl, or check /var/log/syslog and /var/log/auth.log.

6. Check GRE Tunnel:

   • Ensure that the GRE tunnel setup is correct and that the tunnel is up and running. You can use ip tunnel show to verify the tunnel configuration.
   • The script gre.sh is creating a GRE tunnel. Ensure that the remote endpoint 5.230.205.35 is correct and reachable.

7. Check ARP and MAC Addresses:

   • Use arp -a and ip neigh to check the ARP table for correct MAC to IP mappings.

Source: GPT4.