I changed my router last night and computers are fine and wireless fine etc. My development web server seemed fine I can access it any my websites and SSH etc however I noticed that I have no internet access.
I have a Ubuntu 18.04 instance with a static IP set however tested with DHCP and had the same situation with SSH etc but no internet access.
I'm guessing my config is in /etc/netplan and not /etc/network/interfaces for this version of ubuntu so have set below configs which seem to give me a working network connection (although i have set both the same as originally I used the latter and it didn't work):
/etc/netplan/01-netcfg.yaml:
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
version: 2
renderer: networkd
ethernets:
eth0:
dhcp4: no
dhcp6: no
addresses: [192.168.1.6/24]
gateway4: 192.168.1.254
nameservers:
addresses: [8.8.8.8,8.8.4.4]
ifconfig:
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.6 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::a60:6eff:fee5:e58b prefixlen 64 scopeid 0x20<link>
ether 08:60:6e:e5:e5:8b txqueuelen 1000 (Ethernet)
RX packets 29347 bytes 3199867 (3.1 MB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4103 bytes 484556 (484.5 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
/sbin/route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
default 192.168.1.254 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
curl 192.168.1.254:
curl: (7) Failed to connect to 192.168.1.254 port 80: No route to host
Ping fails to 8.8.8.8 and my gateway/router however works to other devices on the network. My new Draytek just doesn't seem to like my server. Nothing seems to show relating to my Server within syslog for the router so feel firewall isn't blocking anything there either. Firewall is also disabled on Ubuntu I believe:
ufw status
Status: inactive
Further investigations show from the router itself I can only ping a few machines not sure what this means but from the Ubuntu box i can ping different machines.
Ping out of Ubuntu 18.04
192.168.1.6 > 192.168.1.20 Ping OK
192.168.1.6 > 192.168.1.254 No Ping
192.168.1.6 > 192.168.1.1 Ping Ok
192.168.1.6 > 192.168.1.53 No Ping
Ping out of Router (Draytek 2960)
192.168.1.254 > 192.168.1.20 No Ping
192.168.1.254 > 192.168.1.6 No Ping
192.168.1.254 > 192.168.1.1 Ping OK
192.168.1.254 > 192.168.1.53 No Ping
Ping out of my Windows Machines
192.168.1.53 > 192.168.1.20 Ping OK
192.168.1.53 > 192.168.1.6 Ping OK
192.168.1.53 > 192.168.1.254 Ping OK
192.168.1.53 > 192.168.1.1 Ping OK
So Windows machine seems happy just some devices non windows ones don't seem to be playing ball with router. The 1.20 is a printer and 1.1 the main domain server here.
TCPDUMP results:
sudo tcpdump -i eth0 icmp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
12:38:12.353881 IP 192.168.1.53 > 192.168.1.6: ICMP echo request, id 1, seq 25, length 40
12:38:12.353922 IP 192.168.1.6 > 192.168.1.53: ICMP echo reply, id 1, seq 25, length 40
12:38:13.357746 IP 192.168.1.53 > 192.168.1.6: ICMP echo request, id 1, seq 26, length 40
12:38:13.357769 IP 192.168.1.6 > 192.168.1.53: ICMP echo reply, id 1, seq 26, length 40
12:38:14.365890 IP 192.168.1.53 > 192.168.1.6: ICMP echo request, id 1, seq 27, length 40
12:38:14.365917 IP 192.168.1.6 > 192.168.1.53: ICMP echo reply, id 1, seq 27, length 40
12:38:15.372843 IP 192.168.1.53 > 192.168.1.6: ICMP echo request, id 1, seq 28, length 40
12:38:50.417412 IP 192.168.1.254 > 192.168.1.6: ICMP echo request, id 40319, seq 0, length 64
12:38:51.417819 IP 192.168.1.254 > 192.168.1.6: ICMP echo request, id 40319, seq 1, length 64
12:38:52.418246 IP 192.168.1.254 > 192.168.1.6: ICMP echo request, id 40319, seq 2, length 64
12:38:53.418592 IP 192.168.1.254 > 192.168.1.6: ICMP echo request, id 40319, seq 3, length 64
12:38:54.419015 IP 192.168.1.254 > 192.168.1.6: ICMP echo request, id 40319, seq 4, length 64
12:46:36.801414 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 1, length 64
12:46:37.801809 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 2, length 64
12:46:38.821929 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 3, length 64
12:46:39.845948 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 4, length 64
12:46:40.869947 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 5, length 64
12:46:41.869836 IP 192.168.1.6 > 192.168.1.53: ICMP echo request, id 28880, seq 6, length 64
First was from Windows to the Ubuntu Box. Then from Router to Ubuntu box. I did try from Ubuntu box to the router however nothing shows in TCPDUMP. The next was from Ubuntu box to Windows machine and requests can be seen going out although no replies as ICMP probably blocked on Windows Defender Firewall.
Any recommendations of what to try here as am out of ideas myself and none of the above makes much sense as to why different devices are PINGABLE from each machine and SSH and PING HTTP all seem to work / not work depending on source?
tcpdump -i eth0 arp -n
14:32:29.414036 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:29.414274 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:29.852626 ARP, Request who-has 192.168.1.200 tell 192.168.1.1, length 46
14:32:29.852643 ARP, Request who-has 192.168.1.58 tell 192.168.1.1, length 46
14:32:30.437906 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:30.438138 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:31.461904 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:31.462138 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:32.486027 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:32.486250 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:33.513904 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:33.514218 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:33.944646 ARP, Request who-has 192.168.1.70 tell 192.168.1.253, length 46
14:32:34.533906 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:34.534222 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
14:32:35.557980 ARP, Request who-has 192.168.1.254 tell 192.168.1.6, length 28
14:32:35.558187 ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
183 packets captured
200 packets received by filter
17 packets dropped by kernel
Mac address of router seems correct with 00:1d:aa:c6:44:68. A lot of the requests however do not show a reply not sure if this is correct?
There are however these showing:
14:55:29.130114 ARP, Unknown (512)
0x0000: 0001 0800 0604 0200 001d aac6 4468 c0a8 ............Dh..
0x0010: 01fe ffff ffff ffff 0000 0000 0100 0000 ................
0x0020: 0000 0000 0000 0000 0000 ..........
14:55:29.130427 ARP, Unknown (512)
0x0000: 0001 0800 0604 0200 001d aac6 4468 c0a8 ............Dh..
0x0010: 02fe ffff ffff ffff 0000 0000 0100 0000 ................
0x0020: 0000 0000 0000 0000 0000
tcpdump -eqtnni eth0 arp
08:60:6e:e5:e5:8b > ff:ff:ff:ff:ff:ff, ARP, length 42: Request who-has 192.168.1.254 tell 192.168.1.6, length 28
00:1d:aa:c6:44:68 > 08:60:6e:e5:e5:8b, 802.1Q, length 60: vlan 1, p 0, ethertype ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
08:60:6e:e5:e5:8b > ff:ff:ff:ff:ff:ff, ARP, length 42: Request who-has 192.168.1.254 tell 192.168.1.6, length 28
00:1d:aa:c6:44:68 > 08:60:6e:e5:e5:8b, 802.1Q, length 60: vlan 1, p 0, ethertype ARP, Reply 192.168.1.254 is-at 00:1d:aa:c6:44:68, length 42
00:1d:aa:c6:44:68 > ff:ff:ff:ff:ff:ff, 802.1Q, length 60: vlan 1, p 0, ethertype ARP, Unknown (512)
0 Answers