Help: Problem with routing between internal network addresse

RouterOS General
1

Very Strange
I have 3 Class Cs(/24) internally
1.1.1.x
2.2.2.x
3.3.3.x

When pinging from a macine 3.3.3.x to an one on 1.1.1.x and 2.2.2.x i get the output below. Why does the router respond back like this ? Gateway of 3.3.3.x is 3.3.3.1(Mikrotik). This started when i upgraded from 2.9.28 to 2.9.46

rom 1.1.1.3: icmp_seq=13 ttl=63 time=2.397 ms
64 bytes from 1.1.1.3: icmp_seq=14 ttl=63 time=1.868 ms
92 bytes from router (3.3.3.1): Redirect Host(New addr: 1.1.1.3)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 d94d 0 0000 40 01 f53a 209.120.245.58 1.1.1.364 bytes from 1.1.1.3: icmp_seq=15 ttl=63 time=4.394 ms
64 bytes from 1.1.1.3: icmp_seq=16 ttl=63 time=2.363 ms
64 bytes from 1.1.1.3: icmp_seq=17 ttl=63 time=3.737 ms


ping 2.2.2.100
PING 2.2.2.100 (2.2.2.100): 56 data bytes
92 bytes from router (3.3.3.1): Redirect Host(New addr: 2.2.2.100)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 95a0 0 0000 40 01 47c7 209.120.245.58 2.2.2.100

64 bytes from 2.2.2.100: icmp_seq=0 ttl=63 time=1.918 ms
92 bytes from router (3.3.3.1): Redirect Host(New addr: 2.2.2.100)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 9853 0 0000 40 01 4514 209.120.245.58 2.2.2.100

64 bytes from 2.2.2.100: icmp_seq=1 ttl=63 time=1.695 ms
92 bytes from router (3.3.3.1): Redirect Host(New addr: 2.2.2.100)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 9b17 0 0000 40 01 4250 209.120.245.58 2.2.2.100

64 bytes from 2.2.2.100: icmp_seq=2 ttl=63 time=3.229 ms
92 bytes from router (3.3.3.1): Redirect Host(New addr: 2.2.2.100)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 9e03 0 0000 40 01 3f64 209.120.245.58 2.2.2.100
64 bytes from 2.2.2.100: icmp_seq=3 ttl=63 time=2.715 ms
92 bytes from router (3.3.3.1): Redirect Host(New addr: 2.2.2.100)
Vr HL TOS Len ID Flg off TTL Pro cks Src Dst
4 5 00 0054 a029 0 0000 40 01 3d3e 209.120.245.58 2.2.2.100
64 bytes from 2.2.2.100: icmp_seq=4 ttl=63 time=2.496 ms
— 2.2.2.100 ping statistics —
5 packets transmitted, 5 packets received, 0% packet loss
round-trip min/avg/max/stddev = 1.695/2.411/3.229/0.552 ms

Any idea why this is happening or what should be done

2

where did you get 2.9.46 :open_mouth:

3

this is called ICMP redirect - a router (default gateway) inform your PC that the packet to 1.1.1.3 can be send from your PC directly to the 1.1.1.3 not only via the gateway. If sender support ICMP redirect it will temporarilly send the packets directly to 1.1.1.3.
The router can generate ICMP redirect when a packet is send out of the box via the same interface it was received on…

I would like to know if this is a new behavior of mikrotik (I think it isn’t because I think I saw it formerly too). And how to disable the ICMP redirect sending and accepting?

4

Typo 44

5

I never saw it earlier it only started after I upgraded to the latest .44 . How do I disable this?