Luxul Switchs and Network Topology

[Severo]

Hi all.

 

I started working at a new company this month and they have Domotz Pro within a Luxul Epic 5 ABR-5000. 
The network used to be 192.168.200.0/24 but they changed recently to 172.16.0.0/16. I read that Domotz won't monitor networks below /22, so I added 172.16.1.0/24 as private subnet in order to solve this issue. Now all our servers and switchs are available in devices list. 
The problem now is Network Topology. Since the last change, it doesn't work. All devices have SNMP v2c enabled. 

 

So my question is: Network topology is not working due to /16 netmask ?

[Giancarlo]

1 minute ago, Severo said:

Hi all.

 

I started working at a new company this month and they have Domotz Pro within a Luxul Epic 5 ABR-5000. 
The network used to be 192.168.200.0/24 but they changed recently to 172.16.0.0/16. I read that Domotz won't monitor networks below /22, so I added 172.16.1.0/24 as private subnet in order to solve this issue. Now all our servers and switchs are available in devices list. 
The problem now is Network Topology. Since the last change, it doesn't work. All devices have SNMP v2c enabled. 

 

So my question is: Network topology is not working due to /16 netmask ?

 

Actually, when adding a "private subnet" to be scanned, the tool scans that part of the network with a Layer 3 only approach (i.e. MAC addresses are not retrieved). Without MAC addresses the automatic-port mapping (which is the backbone of the Network Topology) cannot perform association of Switch Ports with physical devices.

 

We are working on the possibility of adding External Private Subnets on Layer 2 (when the subnets are part of a wider network - as in your case): in this case, the tool will be able to extract MAC addresses and therefore re-create the topology. 

 

In the short terms, the recommendation is to revery back to a smaller network (max /22). Do you really need a /16 network (>1M devices on the same network)?

 

[Severo]

Hi Giancarlo.
a /16 network is not really necessary. I will set a /22 network. This way I can keep ip address for main devices.
 

Thanks for the help. 

[JohnButare]

Hi, i just changed my network to a /22 to add a few more hosts (192.168.0.0/22).   After updating the IP's and restarting the Domotz agent on my Synology DNS, the agent only scanned the 192.168.100.X subnet.   It ignored new devices on 101-103.   My read of this thread indicates Domotz should scan 101-103, is this correct?   I know I can work around this by adding private subnets, but I do not want to do without the lack of MAC address discovery on the private subnets.  Should this work?  Do I need to manually configure or re-install the Domotz agent on the Synology NAS?   Do I need to use a different agent platform such as Raspberry Pi?   Thanks, John

 

5 minutes ago, JohnButare said:

Hi, i just changed my network to a /22 to add a few more hosts (192.168.0.0/22).   After updating the IP's and restarting the Domotz agent on my Synology DNS, the agent only scanned the 192.168.100.X subnet.   It ignored new devices on 101-103.   My read of this thread indicates Domotz should scan 101-103, is this correct?   I know I can work around this by adding private subnets, but I do not want to do without the lack of MAC address discovery on the private subnets.  Should this work?  Do I need to manually configure or re-install the Domotz agent on the Synology NAS?   Do I need to use a different agent platform such as Raspberry Pi?   Thanks, John

 

Sorry, my fault.   I forgot to update the subnet mask on the NAS, all is working as expected now without private subnets.   John

[Giancarlo]

Thanks for following up on this.