ping - missing routing-table

RouterOS RouterOS beta
1

Hi,

in RouterOS 6 I have a running script that checks the status of the main and backup links. It works as follows (the script is quite complex, but it comes down to executing the command):

ping 8.8.8.8 interval=300ms routing-table=internet1
ping 8.8.8.8 interval=300ms routing-table=internet2

For proper operation, the following entries are necessary:

/ip route
add distance=1 gateway=172.16.0.1 routing-mark=internet1
add distance=2 routing-mark=internet1 type=blackhole
add distance=1 gateway=172.16.100.1 routing-mark=internet2
add distance=2 routing-mark=internet2 type=blackhole

add distance=1 gateway=172.16.0.1 comment="wan_monitoring: internet1" disabled=no
add distance=2 gateway=172.16.100.1 comment="wan_monitoring: internet2" disabled=yes
# the script switches the last two commands depending on which link is active

/ip firewall mangle
add action=mark-connection chain=input comment=WAN1_main in-interface=\
    WAN1_main new-connection-mark=MWAN1 passthrough=yes
add action=mark-routing chain=output connection-mark=MWAN1 new-routing-mark=\
    internet1 passthrough=no
add action=mark-connection chain=forward comment=WAN1PF connection-state=new \
    in-interface=WAN1_main new-connection-mark=PFMWAN1 passthrough=yes
add action=mark-routing chain=prerouting connection-mark=PFMWAN1 \
    in-interface=bridge1 new-routing-mark=internet1 passthrough=yes

add action=mark-connection chain=input comment=WAN2_T-Mobile in-interface=\
    WAN2_T-Mobile new-connection-mark=MWAN2 passthrough=yes
add action=mark-routing chain=output connection-mark=MWAN2 new-routing-mark=\
    internet2 passthrough=no
add action=mark-connection chain=forward comment=WAN2PF connection-state=new \
    in-interface=WAN2_T-Mobile new-connection-mark=PFMWAN2 passthrough=yes
add action=mark-routing chain=prerouting connection-mark=PFMWAN2 \
    in-interface=bridge1 new-routing-mark=internet2 passthrough=yes

After upgrading to RouterOS 7, this method no longer works because the ping command no longer has the: routing-table parameter. How in RouterOS 7 can I ping with two different internet connections - use the first one once, and then the second when the first or the second is active?

2

I don’t know what’s the correct, officially recommended solution, but it seems that you can add empty VRF:

/ip vrf add interfaces=none name=internet1

It will create routing table with same name, which you can use for creating routes, and then you can use vrf=internet1 for ping.

3

I fail, I don’t quite understand it yet. Can You write to me how to specifically do this in RouterOS 7: two internet links (if the first ISP is active, the second ISP is disabled), and I’d like to be able to ping any address with each of them.

4

As I wrote, I don’t know what’s the right way. Ping in v7 doesn’t have routing-table parameter anymore, but it has vrf parameter. So I just came up with a quick way how to use that, and it seems to work. In v7 you have to manually create routing tables in “/routing table”, but you can skip that and create them using VRF instead. That’s the command I posted, which will create dynamic routing table (which can then be used same way as static one). And that’s it. I’m not sure that I like it, and I don’t know if there could be some unexpected problems with it. Hopefully someone more knowledgeable will comment on that.

5

Here’s my wan checking scripts updated to work with ros v7. It’s not perfect (improvements welcome) and is going to need some adaptation, but maybe some of it helps you

pppoe

:global pppoe1up
:global pppoe1forceoff
:global pppoe1lastip1
:global pppoe1lastip2

:if ([/interface/pppoe-client/get pppoe1 running]=true) do={
  :local ipfresh1 [/ip/address/get [/ip/address/find where interface=pppoe1] address]
  :local ipfresh2
  if ($pppoe1lastip1 != $ipfresh1) do={
    log error ("pppoe1 IP changed")
    :if ([ :typeof $ipfresh1 ] != nil ) do={
      :for i from=( [:len $ipfresh1] - 1) to=0 do={
        :if ( [:pick $ipfresh1 $i] = "/") do={
          :set ipfresh2 [:pick $ipfresh1 0 $i];
        }
      }
    }
    global pppoe1lastip1 $ipfresh1
    global pppoe1lastip2 $ipfresh2
  }
  :if ($pppoe1up != true && $pppoe1up != false) do={ :global pppoe1up true }
  :if ($pppoe1forceoff = true)  do={
    :if ($pppoe1up = true) do={
      :log error "pppoe1 MARKED OFFLINE!"
      :set pppoe1up false
      /ip/route/set [/ip/route/find where comment=pppoe1 disabled=no] disabled=yes
      /system/script/run flush_wanconn
    }
  } else={
    :local count [/ping address="1.1.1.1" interface="pppoe1" src-address="$pppoe1lastip2" size=28 interval=0.1 count=50]
    :if ($count < 30) do={
      :if ($pppoe1up = true) do={
        :log error "pppoe1 MARKED OFFLINE!"
        :set pppoe1up false
        /ip/route/set [/ip/route/find where comment=pppoe1 disabled=no] disabled=yes
        /system/script/run flush_wanconn
      }
    } else={
      :if ($pppoe1up = false) do={
        :log error "pppoe1 MARKED ONLINE!"
        :set pppoe1up true
        /ip/route/set [/ip/route/find where comment=pppoe1 disabled=yes] disabled=no
        /system/script/run flush_wanconn
      } else={
        :if ([/ip/route/find where comment=pppoe1 disabled=yes]) do={
          :log error "pppoe1 ONLINE BUT ROUTES DISABLED! RE-ENABLING..."
          /ip/route/set [/ip/route/find where comment=pppoe1 disabled=yes] disabled=no
        }
      }
    } 
  }
} else={
  :if ($pppoe1up = true) do={
    :log error "pppoe1 MARKED OFFLINE!"
    :set pppoe1up false
    /ip route set [/ip route find where comment=pppoe1 disabled=no] disabled=yes
    /system/script/run flush_wanconn
  }
}

External (routed) gateway:

:global lte1up
:global lte1forceoff

:if ([/interface/ethernet/get ether3_lte running]=true) do={
  :if ($lte1up != true && $lte1up != false) do={ :global lte1up true }
  :if ($lte1forceoff = true)  do={
    :if ($lte1up = true) do={
      :log error "lte1 MARKED OFFLINE!"
      :set lte1up false
      /ip/route/set [/ip/route/find where comment=lte1 disabled=no] disabled=yes
    /system/script/run flush_wanconn
    }
  } else={
    :local count [/ping address="1.1.1.1" interface="ether3_lte" src-address="192.168.8.2" size=28 interval=1 count=5]
    :if ($count < 2) do={
      :if ($lte1up= true) do={
        :log error "lte1 MARKED OFFLINE!"
        :set lte1up false
        /ip/route/set [/ip/route/find where comment=lte1 disabled=no] disabled=yes
        /system/script/run flush_wanconn
      }
    } else={
      :if ($lte1up= false) do={
        :log error "lte1 MARKED ONLINE!"
        :set lte1up true
        /ip/route/set [/ip/route/find where comment=lte1 disabled=yes] disabled=no
        /system/script/run flush_wanconn
      } else={
        :if ([/ip/route/find where comment=lte1 disabled=yes]) do={
          :log error "lte1 ONLINE BUT ROUTES DISABLED! RE-ENABLING..."
          /ip/route/set [/ip/route/find where comment=lte1 disabled=yes] disabled=no
        }
      }
    }
  } 
} else={
  :if ($lte1up= true) do={
    :log error "lte1 MARKED OFFLINE!"
    :set lte1up false
    /ip route set [/ip route find where comment=lte1 disabled=no] disabled=yes
    /system/script/run flush_wanconn
  }
}

The second type needs some additional config:

/routing/table add disabled=no fib name=check_lte1
/routing/rule add action=lookup disabled=no dst-address=1.1.1.1/32 src-address=192.168.8.2/32 table=check_lte1
/ip/route add comment="internet check" disabled=no distance=1 dst-address=0.0.0.0/0 gateway=192.168.8.1 routing-table=check_lte1

Looking at how much code is needed to achieve this kind of functionality, I feel there should be an easier way to handle this. I know about netwatch, but netwatch does not let you choose the same host for multiple interfaces or have the same customizability of trigger conditions for the ping,

6

Holy flying spaghetti monster, thanks a lot for that.
It never occurred to me that you could use none as a VRF interface and setting it to anything complete moved all ingress traffic from that interface to the VRF.
Using none I’ve emulated ROS6-style simple routing-table functionality.

7

Has anyone had success getting this working for a PPP interface such as those used for USB 4G modems that aren’t able to use the LTE mode?

8

It seems like you can use

ping destination interface=xxxx

And it fails if it can’t reach destination via that interface.
(traceroute tries, but will use whatever is available if doesn’t work via interface though)

9

That works - thanks!