tracert loop

RouterOS Beginner Basics
1

Hi guys

I have a tracert loop for 3 subnets…

#      DST-ADDRESS        PREF-SRC        GATEWAY            DISTANCE
 0 A S  ;;; core route
        0.0.0.0/0                          202.20.4.101              1
20 ADC  202.68.89.152/29   202.68.89.153   bri-vlan51                0
21 ADC  202.68.89.176/28   202.68.89.177   bri-vlan50                0

If you tracert to any of those subnet’s ips you will get stuck in a loop. What do I need to do to fix this?

2

Don’t route loop network. :smiley: Trace the route, and see why its “sended” back. Change the dst address to this “router” Most common loop is the simple R1-R2-R3. Then R1 will have R3 as gateway for traffic coming from R2. R3 will send to R2 again, and you have a loop that will bunch back to r3-r2-r1-r3-r2-r1 etc etc etc.

3

I have to add the addresses of those subnets in order for machines attached to use the public ip addresses directly. They are assigned to vlans which create the routes. If I disable them, the machines cannot use those addresses.

4

Can you post routing setup for all devices?

5

So, the main routing is what I posted above. Attached devices will then use a public address like 202.68.89.188 gw 202.68.89.177 (router)

6

Your post, show a default route. and 2 subnet connected to the router. It does not show the routing information to the devices connected to your subnet, and or routing table of your default gateway.

The new post tells me:

bri-vlan50 have a device connected with ip 202.68.89.188 and default route 202.68.89.187. Then .187 is gateway for the .186/28 network.

When traffic come from .186/28 to .187, as the gatway, the router have 2 choice. If dst address is inside 202.68.89.152/29 interface 152 will be used. If dst address is anything else, 202.20.4.101 will be the gatway. This don’t make a loop. Unless 202.20.4.101 somehow sends traffic back to your router.


You have no info about 202.68.89.152/29

How do you trace the route that loop? From what device (ip) to what device (ip).

7

All the routes I’ve shown are all the routes that are there. If you do a tracert, you will see the loop yourself.

Since the default route is going to 101, I don’t get how there would be a loop in the network.

Tracing route to account.filecloud.co.nz [202.20.2.68]
over a maximum of 30 hops:

  1     *        *        *     Request timed out.
  2    <1 ms    <1 ms    <1 ms  core.layer3.net.nz [202.68.89.177]
  3     2 ms     1 ms     2 ms  dts.net.nz [202.20.4.101]
  4     1 ms     2 ms     2 ms  core.layer3.net.nz [202.68.89.177]
  5     2 ms     2 ms     3 ms  dts.net.nz [202.20.4.101]
  6     3 ms     2 ms     3 ms  core.layer3.net.nz [202.68.89.177]
  7     5 ms     4 ms     3 ms  dts.net.nz [202.20.4.101]
  8     4 ms     3 ms     3 ms  core.layer3.net.nz [202.68.89.177]
  9     4 ms     4 ms     4 ms  dts.net.nz [202.20.4.101]
 10     4 ms     6 ms     4 ms  core.layer3.net.nz [202.68.89.177]
8

how is routingtable for 202.20.4.101

9

I don’t know, that’s my ISPs router.

10

Then your ISP route back to you.