Hi All,
This has been driving me crazy for days, so I hope someone can help.
I have a SG350 (latest firmware: dated March 2021) with three VLANs defined, each with an IP assigned to the VLAN Interface:
- VLAN 10 (192.168.10.2/24)
- VLAN 20 (192.168.20.1/24)
- VLAN 30 (192.168.30.1/24).
IPv4 Routing is turned On.
There are no ACLs in place.
The default gateway for VLAN 10 is a (NetComm) gateway router on 192.168.10.1, which has a static route defined as:
| Destination IP/Mask | Gateway | Interface |
| 192.168.0.0/16 | 192.168.10.2 | br0 |
The Forwarding Table on the SG350 has:
| Destination IP Prefix | Prefix Length | Route Type | Next Hop Router IP Address | Route Owner | Metric | Administrative Distance | Outgoing Interface |
| 0.0.0.0 | 0 | Remote | 192.168.10.1 | Static | 4 | 1 | VLAN 10 |
| 192.168.10.0 | 24 | Local | 192.168.10.2 | Directly Connected | | | VLAN 10 |
| 192.168.20.0 | 24 | Local | 192.168.20.1 | Directly Connected | | | VLAN 20 |
| 192.168.30.0 | 24 | Local | 192.168.30.1 | Directly Connected | | | VLAN 30 |
I have two hosts on each VLAN: (192.168.x.11 & 192.168.x.12)
I have confirmed the following:
- Host .10.11 can ping Host .10.12
- Host .10.11 can ping SVI .10.2
- Host .10.11 can ping Gateway .10.1
- Host .10.12 can ping .10.11
- Host .10.12 can ping SVI .10.2
- Host .10.12 can ping Gateway .10.1
- SVI .10.2 can ping Hosts .10.11 & .10.12
- SVI .10.2 can ping Gateway .10.1
- Gateway .10.1 can ping Hosts .10.11 & .10.12
- Gateway .10.1 can ping SVI .10.2
- Host .20.11 can ping .20.12
- Host .20.11 can ping SVI .20.1
- Host .20.12 can ping .20.11
- Host .20.12 can ping SVI .20.1
- SVI .20.1 can ping Hosts .20.11 & .20.12
- Host .30.11 can ping .30.12
- Host .30.11 can ping SVI .30.1
- Host .30.12 can ping .30.11
- Host .30.12 can ping SVI .30.1
- SVI .30.1 can ping Hosts .30.11 & .30.12
Or, in other words, all intra-VLAN pings work as expected. Also:
- SVI .20.1 can ping all Hosts, all SVIs, and the Gateway .10.1
- SVI .30.1 can ping all Hosts, all SVIs, and the Gateway .10.1
- All Host on VLAN 20 & 30 can ping all Hosts on VLAN 20 & 30
- VLAN 10 has full Internet Access
However:
- Hosts on VLAN 20 & 30 *cannot* ping anything on VLAN 10
- Hosts on VLAN 10, SVI .10.2, and Gateway .10.1 *cannot ping* Hosts on VLAN 20 & 30.
- VLAN 20 & 30 do not have Internet Access
Thus, I suspect I have some sort of "routing conflict" between the SG350 and the NetComm Gateway. Can someone (anyone!) please point this conflict out to me, because I'm buggered if I can find it (buggered = Australian slang for tired, broken, an annoying thing - take your pick).
Or, if my troubleshooting assumption is wrong, could someone please let me know what is the issue, and how to fix it.
Thanks in advance
Dulux-Oz
