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12-02-2019 11:28 AM - edited 12-02-2019 12:14 PM
Hi All,
Please bear with me as I'm new to this and relatively new to Networking at this level.
I'm trying to set up inter VLAN routing. Following this post:
I've configured everything I could (or perhaps almost everything except for 6) Configure the interface to the default router. part. ). This is an older Cisco 3750G switch:
VLAN1 192.168.0 (IP 192.168.0.3, Secondary 192.168.0.4)
VLAN2 10.0.0.0 ( IP 10.0.0.1 )
VLAN3 10.1.0.0 ( IP 10.1.0.1 )
VLAN4 10.2.0.0 ( IP 10.2.0.1 )
Now from the switch itself, I can ping all IP's without any issues. For example, I can ping 192.168.0.100 from the switch but not from within VLAN 2 devices. However, I can ping 192.168.0.3 and 192.168.0.4 (secondary), the switch VLAN 1 IP's from within devices on VLAN 2.
Devices on VLAN2 can ping each other, the VLAN IP and even the default VLAN (Switch IP) 192.168.0.3 and 192.168.0.4 above. But nothing beyond the two VLAN 1 IP's above. What am I missing? My first thought is missing trunking or a setting on VLAN1 but I'm not 100% on that nor what those commands would be.
Thx,
mdscisco01#show ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is 192.168.0.1 to network 0.0.0.0 10.0.0.0/24 is subnetted, 1 subnets C 10.0.0.0 is directly connected, Vlan2 C 192.168.0.0/24 is directly connected, Vlan1 S* 0.0.0.0/0 [1/0] via 192.168.0.1 mdscisco01#
Solved! Go to Solution.
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12-03-2019 08:20 PM - edited 12-04-2019 07:33 PM
So I've managed to solve this issue. Based on my config, to summarize, I had the following:
Asus Router: 192.168.0.1
Cisco 3750: 192.168.0.3, 192.158.0.4 (secondary)
Server 1: 192.168.0.101
Server 2: 10.1.0.73
Server 3: 10.0.0.72
.
.
Apparently why I couldn't reach VLAN 1 (192.168.0.X ) from any other VLAN (2, 3, 4 etc) is because each of my devices on VLAN 1 had a Gateway of 192.168.0.1. And that was the Asus router. As my tcpdump confirmed, the pings were making it out and the clients on 192.168.0.X network did reply correctly, but the ICMP reply went nowhere. Apparently the replies terminated on the Asus router. I couldn't get proper monitoring configured on the Cisco 3750G yet to confirm if any made it to the Cisco switch.
The Asus router at 192.168.0.1, knew nothing about inter-VLAN routing or SVI's etc. So what I did is to change the IP's of my router and the one assigned to the Cisco switch. Now things looked like this:
Asus Router: 192.168.0.6
Cisco 3750: 192.168.0.1, 192.158.0.2 (secondary)
Server 1: 192.168.0.101
Server 2: 10.1.0.73
Server 3: 10.0.0.72
.
.
So now my gateway was the Cisco switch. As soon as that happened, everything worked perfect. Was able to ping devices across the VLAN's without any issue. But the internet access wouldn't work. To fix that, I simply changed the Gateway of last resort like this:
mdscisco01(config)#ip route 0.0.0.0 0.0.0.0 192.168.0.6
mdscisco01#show ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is 192.168.0.6 to network 0.0.0.0 10.0.0.0/24 is subnetted, 2 subnets C 10.0.0.0 is directly connected, Vlan2 C 10.1.0.0 is directly connected, Vlan3 C 192.168.0.0/24 is directly connected, Vlan1 S* 0.0.0.0/0 [1/0] via 192.168.0.6 [1/0] via 192.168.0.1 mdscisco01#
Wrote up the experience here: Cisco 3750G Intervlan Routing .
Thank you all for helping out with this. Your suggestions left me with valuable clues that helped out here.
Thx,
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12-04-2019 03:02 PM
Please, check it:
!
no ip default-gateway 192.168.0.3
I think that your Asus is not enabled OSPF then it will not work.
I suggest to your first, create a three static route in your ASUS and test again, like below;
ip route 10.0.0.1 255.255.255.0 192.168.0.1
ip route 10.1.0.0 255.255.255.0 192.168.0.1
ip route 10.2.0.0 255.255.255.0 192.168.0.1
ip route 10.3.0.0 255.255.255.0 192.168.0.1
if it work, try enable OSPF in your ASUS ROUTER and remove this static routes and test again..
Regards,
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12-04-2019 07:42 PM - edited 12-04-2019 08:07 PM
Per an earlier ask, moving content from Echo reply not received on gateway of last resort from specific VLAN's here instead. My reply on the above thread is included below.
-------------------------------
Hey All,
My question here follows on my earlier post about Inter VLAN Routing . Using the same diagram, I now have an issue where VLAN 2, 3 and 4 can't reach the web/internet. This occurred after I enabled OSPF for learning purposes. I've also adjusted F/W configuration on my Asus router that initially blocked the pings to any outside address. This didn't fix the main issue though it did fix pinging from 1) The Cisco 3750G and 2) from the Asus router.
However, I still can't ping outside addresses from the above said VLAN's. Below is my diagram again.
VLAN 1: 192.168.0.X / 24
VLAN 2: 10.0.0.X / 24
VLAN 3: 10.1.0.X / 24
VLAN 4: 10.2.0.X / 24
Asus Router: 192.168.0.6
Cisco 3750G: 192.168.0.1 w/ 192.168.0.2 as secondary.
Server 1: 192.168.0.123 ( VLAN 1 )
Server 2: 10.0.0.72 ( VLAN 2 )
Server 3: 10.0.0.73 ( VLAN 2 )
All three servers above are connected to the Cisco switch. Basic network diagram attached.
The issue is as follows.
Pinging 8.8.8.8 works fine from Server1 ( VLAN 1 ):
[root@server1 ~]# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. 64 bytes from 8.8.8.8: icmp_seq=1 ttl=55 time=30.3 ms 64 bytes from 8.8.8.8: icmp_seq=2 ttl=55 time=22.6 ms 64 bytes from 8.8.8.8: icmp_seq=3 ttl=55 time=17.5 ms 64 bytes from 8.8.8.8: icmp_seq=4 ttl=55 time=21.9 ms From 192.168.0.1 icmp_seq=5 Redirect Network(New nexthop: 192.168.0.6) From 192.168.0.1: icmp_seq=5 Redirect Network(New nexthop: 192.168.0.6) 64 bytes from 8.8.8.8: icmp_seq=5 ttl=55 time=33.8 ms From 192.168.0.1 icmp_seq=6 Redirect Network(New nexthop: 192.168.0.6) From 192.168.0.1: icmp_seq=6 Redirect Network(New nexthop: 192.168.0.6) 64 bytes from 8.8.8.8: icmp_seq=6 ttl=55 time=19.8 ms 64 bytes from 8.8.8.8: icmp_seq=7 ttl=55 time=20.5 ms
The New nexthop doesn't appear to be an issue. But the same ping from VLAN 2 fails.
[root@server3 network-scripts]# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. ^C --- 8.8.8.8 ping statistics --- 289 packets transmitted, 0 received, 100% packet loss, time 287999ms
I moved devices from VLAN 3 to VLAN 2 to test this issue so only have devices on VLAN 2 right now. Same issue happened on VLAN 3. Running tcpdump from Server3 shows that the echo request makes it out fine:
Server 3 ( VLAN 2 )
[root@server3 ~]# tcpdump -i onebr01 -n port not 22 and port not 53 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on onebr01, link-type EN10MB (Ethernet), capture size 262144 bytes 16:32:55.132379 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:32:57.139757 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:32:58.051427 IP 10.0.0.1 > 224.0.0.5: OSPFv2, Hello, length 56 16:32:59.142163 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:32:59.209506 Loopback, skipCount 0, Reply, receipt number 0, data (40 octets) 16:33:00.322028 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 27956, seq 1, length 64 16:33:01.146881 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:33:01.321436 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 27956, seq 2, length 64 16:33:02.321437 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 27956, seq 3, length 64 16:33:03.151786 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:33:03.321426 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 27956, seq 4, length 64 16:33:05.156910 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:33:07.164314 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:33:08.059185 IP 10.0.0.1 > 224.0.0.5: OSPFv2, Hello, length 56 16:33:09.166551 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43 16:33:09.209790 Loopback, skipCount 0, Reply, receipt number 0, data (40 octets) 16:33:11.171629 STP 802.1d, Config, Flags [none], bridge-id 8002.00:1c:57:ae:f8:00.8005, length 43
And even makes it out the Asus router:
root@AsusRouter:~# tcpdump -i vlan2 -n port not 22 and port not 53 | grep -Ei "8.8.8.8|10.0.0.73" tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on vlan2, link-type EN10MB (Ethernet), capture size 262144 bytes 17:27:48.630938 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 28149, seq 1, length 64 17:27:49.624087 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 28149, seq 2, length 64 17:27:50.625051 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 28149, seq 3, length 64 17:27:51.623614 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 28149, seq 4, length 64
But nothing comes back. Asus Router F/W logs show nothing blocked in regards to this. Tried disabling F/W on the AsusRouter. Same thing. This used to work before I had OSPF enabled. So I tried to disable OSPF. It didn't work either. (Perhaps I needed to reload the config?)
Of course, pinging from the Cisco switch itself works just fine:
Cisco 3750G
cisco01#ping 8.8.8.8 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 16/18/25 ms cisco01#
Interestingly, on same said Server3, name resolution works, but I'm using an internal DNS server that doesn't have this external ping problem, so not too surprised by this:
[root@server3 ~]# ping mirrorlist.centos.org PING mirrorlist.centos.org (67.219.148.138) 56(84) bytes of data. ^C --- mirrorlist.centos.org ping statistics --- 31 packets transmitted, 0 received, 100% packet loss, time 29999ms [root@server3 ~]#
What could be the issue here? I've included my Cisco 3750G configuration below. Perhaps the packets are dropped on the remote host due to being invalid? I was thinking the Asus router might be missing a route but then I would expect to see an echo reply appearing on the Asus router. But it's not.
My knowledge of OSPF is also very basic.
Thx,
Cisco 3750G Config
cisco01#show running-config Building configuration... Current configuration : 2385 bytes ! version 12.2 no service pad service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname cisco01 ! enable secret 5 <SECRET> enable password <SECRET> ! username cisco password 0 <SECRET> aaa new-model aaa authentication login default local aaa authentication enable default enable ! aaa session-id common switch 1 provision ws-c3750g-24ps system mtu routing 1500 ip subnet-zero ip routing ! ! ! ! ! ! ! ! ! spanning-tree mode pvst spanning-tree extend system-id ! vlan internal allocation policy ascending ! ! ! ! interface GigabitEthernet1/0/1 ! interface GigabitEthernet1/0/2 ! interface GigabitEthernet1/0/3 switchport mode access ! interface GigabitEthernet1/0/4 ! interface GigabitEthernet1/0/5 switchport access vlan 2 switchport mode access ! interface GigabitEthernet1/0/6 ! interface GigabitEthernet1/0/7 ! interface GigabitEthernet1/0/8 ! interface GigabitEthernet1/0/9 ! interface GigabitEthernet1/0/10 switchport access vlan 2 switchport mode access ! interface GigabitEthernet1/0/11 ! interface GigabitEthernet1/0/12 ! interface GigabitEthernet1/0/13 ! interface GigabitEthernet1/0/14 ! interface GigabitEthernet1/0/15 ! interface GigabitEthernet1/0/16 ! interface GigabitEthernet1/0/17 ! interface GigabitEthernet1/0/18 ! interface GigabitEthernet1/0/19 ! interface GigabitEthernet1/0/20 ! interface GigabitEthernet1/0/21 ! interface GigabitEthernet1/0/22 ! interface GigabitEthernet1/0/23 ! interface GigabitEthernet1/0/24 switchport access vlan 3 ! interface GigabitEthernet1/0/25 ! interface GigabitEthernet1/0/26 ! interface GigabitEthernet1/0/27 ! interface GigabitEthernet1/0/28 ! interface Vlan1 ip address 192.168.0.2 255.255.255.0 secondary ip address 192.168.0.1 255.255.255.0 ! interface Vlan2 ip address 10.0.0.1 255.255.255.0 ! interface Vlan3 ip address 10.1.0.1 255.255.255.0 ! interface Vlan4 ip address 10.2.0.1 255.255.255.0 ! interface Vlan5 ip address 10.3.0.1 255.255.255.0 ! router ospf 1 log-adjacency-changes network 10.0.0.0 0.0.0.255 area 0 network 10.1.0.0 0.0.0.255 area 0 network 10.2.0.0 0.0.0.255 area 0 network 192.168.0.0 0.0.0.255 area 0 ! ip default-gateway 192.168.0.3 ip classless ip route 0.0.0.0 0.0.0.0 192.168.0.6 ip http server ip http secure-server ! ! radius-server source-ports 1645-1646 ! control-plane ! ! line con 0 line vty 5 15 ! end cisco01#
cisco01#show ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is 192.168.0.6 to network 0.0.0.0 10.0.0.0/24 is subnetted, 2 subnets C 10.0.0.0 is directly connected, Vlan2 C 10.1.0.0 is directly connected, Vlan3 C 192.168.0.0/24 is directly connected, Vlan1 S* 0.0.0.0/0 [1/0] via 192.168.0.6 cisco01#
cisco01#show ip ospf database OSPF Router with ID (192.168.0.1) (Process ID 1) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count 192.168.0.1 192.168.0.1 1599 0x80000006 0x0069D3 4 cisco01#show vlan VLAN Name Status Ports ---- -------------------------------- --------- ------------------------------- 1 default active Gi1/0/1, Gi1/0/2, Gi1/0/3, Gi1/0/4 Gi1/0/6, Gi1/0/7, Gi1/0/8, Gi1/0/9 Gi1/0/11, Gi1/0/12, Gi1/0/13, Gi1/0/14 Gi1/0/15, Gi1/0/16, Gi1/0/17, Gi1/0/18 Gi1/0/19, Gi1/0/20, Gi1/0/21, Gi1/0/22 Gi1/0/23, Gi1/0/25, Gi1/0/26, Gi1/0/27 Gi1/0/28 2 VLAN0002 active Gi1/0/5, Gi1/0/10 3 VLAN0003 active Gi1/0/24 4 VLAN0004 active 5 VLAN0005 active 1002 fddi-default act/unsup 1003 trcrf-default act/unsup 1004 fddinet-default act/unsup 1005 trbrf-default act/unsup VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 ---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------ 1 enet 100001 1500 - - - - - 0 0 2 enet 100002 1500 - - - - - 0 0 3 enet 100003 1500 - - - - - 0 0 4 enet 100004 1500 - - - - - 0 0 5 enet 100005 1500 - - - - - 0 0 1002 fddi 101002 1500 - - - - - 0 0 1003 trcrf 101003 4472 1005 3276 - - srb 0 0 1004 fdnet 101004 1500 - - - ieee - 0 0 1005 trbrf 101005 4472 - - 15 ibm - 0 0 VLAN AREHops STEHops Backup CRF ---- ------- ------- ---------- 1003 7 7 off Remote SPAN VLANs ------------------------------------------------------------------------------ Primary Secondary Type Ports ------- --------- ----------------- ------------------------------------------ cisco01#
-------------------------------
So I tried adding the routes on the Asus Router (w/ DD-WRT).
root@AsusRouter:~# ip route default via 123.123.123.1 dev vlan2 10.0.0.0/24 via 192.168.0.1 dev br0 10.0.1.0/24 via 192.168.0.1 dev br0 10.0.2.0/24 via 192.168.0.1 dev br0 10.0.3.0/24 via 192.168.0.1 dev br0 123.123.123.0/27 dev vlan2 scope link src 108.168.115.11 127.0.0.0/8 dev lo scope link 169.254.0.0/16 dev br0 scope link src 169.254.255.1 192.168.0.0/24 dev br0 scope link src 192.168.0.6 192.168.45.0/24 dev wl0.1 scope link src 192.168.45.1 192.168.75.0/24 dev wl1.1 scope link src 192.168.75.1 root@DD-WRT-INTERNET-ASUS:~#
but it had no effect. I'm not entirely surprised. 8.8.8.8 returns no reply. Can't route something back that isn't there to begin with.
Now, if I ping 8.8.8.8 from the 1) Asus Router or 2) from any host on VLAN 1 ( 192.168.0.X ), ping works. Issue only occurs if I initiate the ping against 8.8.8.8 from VLAN 2, 3, 4.
So it appears to me that when the ICMP travels through VLAN 2, 3, 4 it's changed in some way that causes 8.8.8.8 to drop the packet or simply not reply. That's the only plausible explanation that fits the analysis so far and makes the most sense.
In other words, the echo reply doesn't appear to be sent from 8.8.8.8 if the ping originates from VLAN 2, 3, 4. Please see the Asus router tcpdump above.
By the the way in your OP you have the
Asus as 192.168.0.1
ciscoas 192.168.0.3
on here
Asus as 192.168.0.6
ciscoas 192.168.0.1
That's right. If you notice further up in the post here, to solve the original issue on that post, I changed the Asus router IP from 192.168.0.1 to 192.168.0.6 and then changed the Cisco 3750G IP from 192.168.0.3 and 192.168.0.4 (secondary) to 192.168.0.1 and 192.168.0.2 (secondary) to resolve that issue. This post (now a reply) is a new issue in continuation of the first one. ( Hence why I initially thought to start it as a separate topic. )
@paul driver My answers to the other questions you've had are below. Going by email as I can't find these in the flurry of replies (apologies).
interface GigabitEthernet1/0/24 <----WHY a trunk, why not a access port in vlan 1?
switchport trunk allowed vlan 1-4
In my attempts to resolve the original issue, one theory I had is that trunking wasn't enabled. My Asus router used to be, but is no longer, connected to port G1/0/24. I thought at the time that perhaps traffic from VLAN 2, 3, 4 wasn't being sent through because trunking wasn't enabled on the Cisco to Asus router link. I was wrong and that stayed from that debugging attempt.
interface Vlan1
ip address 192.168.0.4 255.255.255.0 secondary Why do you have this?
It was an option. Since Cisco provided it, I saw no harm filling it in a few years back.
interface Vlan4 ip address 10.2.0.1 255.255.255.0 ! ip default-gateway 192.168.0.1 ip route 0.0.0.0 0.0.0.0 192.168.0.1
vlan 2-4
exit
All access ports
int x/x
switchport mode access
spanning-tree portfast
switchport access vlan xx
Saw no harm leaving the default gateway. It worked fine before with that gateway. Read it wont' be used anyway so felt there's no harm leaving it.
As for the second item, by default, any interfaces not specifically assigned to a VLAN will by default be on VLAN 1. So I only left the defaults on those.
Thx,
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12-05-2019 02:59 AM
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12-05-2019 06:54 AM
NAT rules that I currently have (Note again, I'm running DD-WRT):
root@AsusRouter:~# iptables -t nat -nL Chain PREROUTING (policy ACCEPT) target prot opt source destination DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:17855 to:192.168.0.6:443 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:17856 to:192.168.0.6:50505 DNAT icmp -- 0.0.0.0/0 123.123.123.321 to:192.168.0.6 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:40404 to:192.168.0.40:22 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:40404 to:192.168.0.40:22 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:30000 to:192.168.0.150:443 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:30000 to:192.168.0.150:443 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:13389 to:192.168.0.18:3389 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:13389 to:192.168.0.18:3389 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:19132 to:192.168.0.166:19132 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:19132 to:192.168.0.166:19132 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:443 to:192.168.0.115:443 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:443 to:192.168.0.115:443 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:80 to:192.168.0.212:80 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:80 to:192.168.0.212:80 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:7777 to:192.168.0.212:7777 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:7777 to:192.168.0.212:7777 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:2106 to:192.168.0.212:2106 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:2106 to:192.168.0.212:2106 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:10241 to:192.168.0.212:10241 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:10241 to:192.168.0.212:10241 DNAT tcp -- 0.0.0.0/0 123.123.123.321 tcp dpt:17857 to:192.168.0.104:22 DNAT udp -- 0.0.0.0/0 123.123.123.321 udp dpt:17857 to:192.168.0.104:22 TRIGGER 0 -- 0.0.0.0/0 123.123.123.321 TRIGGER type:dnat match:0 relate:0 Chain INPUT (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination SNAT 0 -- 0.0.0.0/0 0.0.0.0/0 to:192.168.0.6 SNAT 0 -- 192.168.0.0/24 0.0.0.0/0 to:123.123.123.321 SNAT 0 -- 192.168.45.0/24 0.0.0.0/0 to:123.123.123.321 SNAT 0 -- 192.168.75.0/24 0.0.0.0/0 to:123.123.123.321 MASQUERADE 0 -- 0.0.0.0/0 0.0.0.0/0 mark match 0x80000000/0x80000000 MASQUERADE 0 -- 10.1.1.0/24 0.0.0.0/0 root@AsusRouter:~#
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12-05-2019 06:37 AM - edited 12-05-2019 06:43 AM
Hello
Just to summerize , you now have reachability using static addressing between asus and cisco switch for ALL vlans but when you use dynamic routing(OSPF) it fails for all vlans or just specific ones?
FYI- secondary addressing can cause unwarranted issues and for routing purposes only the primary ip address is used so it if isnt required remove it
Also..
interface Vlan1
ip address 192.168.0.2 255.255.255.0 secondary ,---remove this please
ip address 192.168.0.1 255.255.255.0 <-- thought this was .3 now ?
Cisco
no router ospf 1
router ospf 1
passive interface default
no passive interface vlan 1
network 192.168.0.3 0.0.0.0 area 0
network 10.0.0.1 0.0.0.0 area 0
network 10.1.0.1 0.0.0.0 area 0
network 10.2.0.1 0.0.0.0 area 0
network 10.3.0.1 0.0.0.0 area 0
exit
no ip route 0.0.0.0 0.0.0.0 192.168.0.6
ip route 0.0.0.0 0.0.0.0 vlan 1 192.168.0.6
sh ip ospf neighbors
sh ip ospf route
Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.
Kind Regards
Paul

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12-05-2019 06:58 AM - edited 12-05-2019 07:08 AM
ip address 192.168.0.1 255.255.255.0 <-- thought this was .3 now ?
No, my current config is:
Asus Router: 192.168.0.6
Cisco 3750G: 192.168.0.1, Secondary: 192.168.0.2
192.168.0.3 and 192.168.0.4 are no longer being used. So I'll use the steps below but I'll assume that everywhere you have 192.168.0.3, I'll replace it with 192.168.0.1.
EDIT:
Just saw this question:
Just to summerize , you now have reachability using static addressing between asus and cisco switch for ALL vlans but when you use dynamic routing(OSPF) it fails for all vlans or just specific ones?
Ping to 8.8.8.8 from clients on VLAN 2, 3, 4 returns no response. Pinging 8.8.8.8 from devices on VLAN 1 works fine despite ( An echo reply is received from 8.8.8.8. ) despite the next-hop message:
[root@mdskvm-p02 network-scripts]# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. 64 bytes from 8.8.8.8: icmp_seq=1 ttl=55 time=13.5 ms 64 bytes from 8.8.8.8: icmp_seq=2 ttl=55 time=11.4 ms From 192.168.0.1 icmp_seq=3 Redirect Network(New nexthop: 192.168.0.6) From 192.168.0.1: icmp_seq=3 Redirect Network(New nexthop: 192.168.0.6) 64 bytes from 8.8.8.8: icmp_seq=3 ttl=55 time=12.6 ms 64 bytes from 8.8.8.8: icmp_seq=4 ttl=55 time=11.8 ms

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12-05-2019 08:20 AM - edited 12-05-2019 08:22 AM
I've tried to redo the OSPF configuration as suggested. Some commands didn't work (older version of the software I suppose).
These did not work.
no passive interface vlan 1
sh ip ospf neighbors
sh ip ospf route
Current config:
cisco01#show running-config Building configuration... Current configuration : 2390 bytes ! version 12.2 no service pad service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname cisco01 ! enable secret 5 <SECRET> enable password <SECRET> ! username cisco password 0 <SECRET> aaa new-model aaa authentication login default local aaa authentication enable default enable ! aaa session-id common switch 1 provision ws-c3750g-24ps system mtu routing 1500 ip subnet-zero ip routing ! ! ! ! ! ! ! ! ! spanning-tree mode pvst spanning-tree extend system-id ! vlan internal allocation policy ascending ! ! ! ! interface GigabitEthernet1/0/1 ! interface GigabitEthernet1/0/2 ! interface GigabitEthernet1/0/3 switchport mode access ! interface GigabitEthernet1/0/4 ! interface GigabitEthernet1/0/5 switchport access vlan 2 switchport mode access ! interface GigabitEthernet1/0/6 ! interface GigabitEthernet1/0/7 ! interface GigabitEthernet1/0/8 ! interface GigabitEthernet1/0/9 ! interface GigabitEthernet1/0/10 switchport access vlan 2 switchport mode access ! interface GigabitEthernet1/0/11 ! interface GigabitEthernet1/0/12 ! interface GigabitEthernet1/0/13 ! interface GigabitEthernet1/0/14 ! interface GigabitEthernet1/0/15 ! interface GigabitEthernet1/0/16 ! interface GigabitEthernet1/0/17 ! interface GigabitEthernet1/0/18 ! interface GigabitEthernet1/0/19 ! interface GigabitEthernet1/0/20 ! interface GigabitEthernet1/0/21 ! interface GigabitEthernet1/0/22 ! interface GigabitEthernet1/0/23 ! interface GigabitEthernet1/0/24 switchport mode access spanning-tree portfast ! interface GigabitEthernet1/0/25 ! interface GigabitEthernet1/0/26 ! interface GigabitEthernet1/0/27 ! interface GigabitEthernet1/0/28 ! interface Vlan1 ip address 192.168.0.1 255.255.255.0 ! interface Vlan2 ip address 10.0.0.1 255.255.255.0 ! interface Vlan3 ip address 10.1.0.1 255.255.255.0 ! interface Vlan4 ip address 10.2.0.1 255.255.255.0 ! interface Vlan5 ip address 10.3.0.1 255.255.255.0 ! router ospf 1 log-adjacency-changes network 10.0.0.1 0.0.0.0 area 0 network 10.1.0.1 0.0.0.0 area 0 network 10.2.0.1 0.0.0.0 area 0 network 10.3.0.1 0.0.0.0 area 0 network 192.168.0.1 0.0.0.0 area 0 ! ip default-gateway 192.168.0.1 ip classless ip route 0.0.0.0 0.0.0.0 Vlan1 192.168.0.6 ip http server ip http secure-server ! ! radius-server source-ports 1645-1646 ! control-plane ! ! line con 0 line vty 5 15 ! end cisco01#
Current diagram is attached. I've adjusted it to match the latest issue config.
Looking at the NAT options @Jaderson Pessoa suggested.
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12-05-2019 08:42 AM - edited 12-05-2019 08:45 AM
Hello
So I guess you are saying static or ospf routing internet access is applicable for only vlan 1?
I assume the Asus is aware of your Lans subnets - be it via static routes pointing back towards your cisco switch or them being learnt via opsf from the cisco switch?
If so that leaves Network Translation ( NAT) on the Asus.
Chain POSTROUTING (policy ACCEPT) target prot opt source destination SNAT 0 -- 0.0.0.0/0 0.0.0.0/0 to:192.168.0.6 SNAT 0 -- 192.168.0.0/24 0.0.0.0/0 to:123.123.123.321 SNAT 0 -- 192.168.45.0/24 0.0.0.0/0 to:123.123.123.321 SNAT 0 -- 192.168.75.0/24 0.0.0.0/0 to:123.123.123.321 MASQUERADE 0 -- 0.0.0.0/0 0.0.0.0/0 mark match 0x80000000/0x80000000 MASQUERADE 0 -- 10.1.1.0/24 0.0.0.0/0
I dont see any translation for those other subnets in this output so does your Asus nat configuration need to be updated to accomodate these other vlans - Have you done this?
cisco
Sh ip route
Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.
Kind Regards
Paul

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12-05-2019 09:00 AM
No, was just looking at NAT right now. The DD-WRT config will take a bit more time so focused on the Cisco commands you're posted since that's a quicker win. While looking at the NAT setup, I decided to capture some more packet output. While trying to transfer the packet output to a host on VLAN 2, I couldn't:
root@AsusRouter:~# scp trace-vlan-asusrouter.dat 10.0.0.73: ^Croot@DD-WRT-INTERNET-ASUS:~# ping 10.0.0.73 PING 10.0.0.73 (10.0.0.73): 56 data bytes ^C --- 10.0.0.73 ping statistics --- 18 packets transmitted, 0 packets received, 100% packet loss root@AsusRouter:~# ping 10.0.0.73 PING 10.0.0.73 (10.0.0.73): 56 data bytes ^C --- 10.0.0.73 ping statistics --- 14 packets transmitted, 0 packets received, 100% packet loss root@AsusRouter:~#
I traced this:
root@AsusRouter:~# tcpdump -i vlan2 -s 0 -e icmp -n tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on vlan2, link-type EN10MB (Ethernet), capture size 262144 bytes 11:47:38.781063 40:16:7e:a2:62:11 > 00:17:10:90:d1:94, ethertype IPv4 (0x0800), length 98: 123.123.123.321 > 10.0.0.73: ICMP echo request, id 54385, seq 0, length 64 11:47:39.786269 40:16:7e:a2:62:11 > 00:17:10:90:d1:94, ethertype IPv4 (0x0800), length 98: 123.123.123.321 > 10.0.0.73: ICMP echo request, id 54385, seq 1, length 64
but no reply. 123.123.123.321 is the WAN IP on the AsusRouter.
Going to finish implementing the NAT rules and will post back.
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12-05-2019 09:24 AM
1. Nat configuration
2. Route back.
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12-05-2019 10:29 AM
@Jaderson Pessoa , @paul driver
Once again thank you very much gentlemen! Appreciated as always!
And NAT'ing was the issue gentlemen.
root@AsusRouter:~# ping 10.0.0.73
PING 10.0.0.73 (10.0.0.73): 56 data bytes
^C
--- 10.0.0.73 ping statistics ---
2 packets transmitted, 0 packets received, 100% packet loss
root@AsusRouter:~#
root@AsusRouter:~# route add -net 10.0.0.0 netmask 255.255.255.0 gateway 192.168.0.1 root@AsusRouter:~# root@AsusRouter:~# ping 10.0.0.73 PING 10.0.0.73 (10.0.0.73): 56 data bytes 64 bytes from 10.0.0.73: seq=0 ttl=63 time=0.533 ms 64 bytes from 10.0.0.73: seq=1 ttl=63 time=0.335 ms 64 bytes from 10.0.0.73: seq=2 ttl=63 time=0.376 ms ^C --- 10.0.0.73 ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max = 0.335/0.414/0.533 ms root@AsusRouter:~#
Once I did the above, pinging from one of the hosts on VLAN 2 works as it should:
[root@server3 network-scripts]# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. ^C --- 8.8.8.8 ping statistics --- 38 packets transmitted, 0 received, 100% packet loss, time 36999ms [root@server3 network-scripts]# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. 64 bytes from 8.8.8.8: icmp_seq=1 ttl=54 time=13.3 ms 64 bytes from 8.8.8.8: icmp_seq=2 ttl=54 time=13.5 ms 64 bytes from 8.8.8.8: icmp_seq=3 ttl=54 time=18.5 ms ^C --- 8.8.8.8 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2003ms rtt min/avg/max/mdev = 13.337/15.144/18.525/2.396 ms [root@server3 network-scripts]#
And my new routing table:
root@AsusRouter:~# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 123.123.123.101 0.0.0.0 UG 0 0 0 vlan2 10.0.0.0 192.168.0.1 255.255.255.0 UG 0 0 0 br0 10.1.0.0 192.168.0.1 255.255.255.0 UG 0 0 0 br0 10.2.0.0 192.168.0.1 255.255.255.0 UG 0 0 0 br0 123.123.123.100 0.0.0.0 255.255.255.224 U 0 0 0 vlan2 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 br0 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 br0 192.168.45.0 0.0.0.0 255.255.255.0 U 0 0 0 wl0.1 192.168.75.0 0.0.0.0 255.255.255.0 U 0 0 0 wl1.1 root@AsusRouter:~#
I'm not sure however how to reconcile this with the tcpdump command above, however. I guess what I saw with tcpdump on the Asus Router was an attempt to send and nothing else:
root@AsusRouter:~# tcpdump -i vlan2 -n port not 22 and port not 53 | grep -Ei "8.8.8.8|10.0.0.73" tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on vlan2, link-type EN10MB (Ethernet), capture size 262144 bytes 17:27:48.630938 IP 10.0.0.73 > 8.8.8.8: ICMP echo request, id 28149, seq 1, length 64
Next is to try and set Dynamic Routing to OSPF on the Asus Router. I'll do that and report back then spread the points around.
Thx,
TK
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12-05-2019 11:03 AM
Regards,
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12-06-2019 06:44 AM
Hey Guy's, would you happen to know or have come across any reason why a router enabled as a Gateway shouldn't run OSPF?
Trying to confirm what I'm reading on a Gateway configuration page as part of DD-WRT but my understanding of that part of networking is still shady in that area.
Thx,
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12-06-2019 08:44 AM
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