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wolfsbane
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VRRP sync-connection-tracking setup

Tue Sep 15, 2020 12:00 am

Hello,

I am playing around with 7.1beta2 and noticed with VRRP there is an option to enable sync-connection-tracking.
I have not been able to find any documentation on how to configure it. I have it enabled and have the remote IP set to the other router but nothing ever seems to be synced when i look under the firewall connections.

Is there any documentation for this feature or is it still incomplete?
 
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raimondsp
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Re: VRRP sync-connection-tracking setup

Tue Sep 15, 2020 3:51 pm

If VRRP is up and running, then in most cases, simply setting
sync-connection-tracking=yes
on both ends should do the trick: VRRP master syncing its connection with the backup router.

Some useful info / limitations:
  1. MikroTik uses its own proprietary protocol for connection syncing. Therefore, both routers must be MikroTik.
  2. Both routers must be running the same version of RoutersOS v7 (e.g., 7.1beta2).
  3. While VRRP allows multiple backup routers, the connection syncing protocol supports only one (i.e., there must be only two routers: one master + one backup).
  4. VRRP Preemption Mode must be disabled (preemption-mode=no).
  5. The connection syncing protocol uses IPv4 for the internal data channel. In case of IPv6 (v3-protocol=ipv6), remote-address is mandatory.
  6. In case of IPv4, remote-address is optional, however, recommended (reduces VRRP latency).
 
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raimondsp
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Re: VRRP sync-connection-tracking setup

Tue Sep 15, 2020 3:59 pm

If the above information is insufficient, please provide the output of:
/interface export hide-sensitive
/interface/vrrp print detail
from both routers.

If you have a VRRP password set, please manually remove it from the output, since the print command doesn't have a hide-sensitive option.
 
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Re: VRRP sync-connection-tracking setup

Mon Feb 15, 2021 9:34 pm

If VRRP is up and running, then in most cases, simply setting
sync-connection-tracking=yes
on both ends should do the trick: VRRP master syncing its connection with the backup router.

Some useful info / limitations:
  1. MikroTik uses its own proprietary protocol for connection syncing. Therefore, both routers must be MikroTik.
  2. Both routers must be running the same version of RoutersOS v7 (e.g., 7.1beta2).
  3. While VRRP allows multiple backup routers, the connection syncing protocol supports only one (i.e., there must be only two routers: one master + one backup).
  4. VRRP Preemption Mode must be disabled (preemption-mode=no).
  5. The connection syncing protocol uses IPv4 for the internal data channel. In case of IPv6 (v3-protocol=ipv6), remote-address is mandatory.
  6. In case of IPv4, remote-address is optional, however, recommended (reduces VRRP latency).
This is fantastic.... but...
What is the status of "firewall rules" sync between routers?
Or even better - config sync?

Are there any "suggested/verified" methods? There are some user proposed scripts... but nothing "universally useful"...
There is the excellent https://github.com/svlsResearch/ha-mikrotik but that's an active/passive solution requiring reboots for failovers which takes time and drops *any/all* state

Any plans in that regard? What do you suggest to use to have a "proper" HA (with minimal or no loss of connectivity) solution for Mikrotik devices?

Are there any "suggested" centralized management SW where you could edit/modify config to be automatically pushed to "paired" devices? That in combination with vrrp-sync could do the trick...

(if only Mikrotik config handling would allow direct "editing" (injecting/changing a specific <b>line</b> of configuration or some sort of <i>diff</i> apply...)

Any suggestions?
 
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Re: VRRP sync-connection-tracking setup

Tue Feb 16, 2021 12:20 pm

Currently there are several centralised configuration management options: TR069, API, SSH, and now even REST.
 
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Re: VRRP sync-connection-tracking setup

Tue Feb 16, 2021 12:54 pm

Yeah... I know about the "possibilities" or "options" for centralized management...
but are there any "suggested"/Recommended "product/solution" for that purpose?

I know about for ex Unimus and some other similar products and the TR-69 (Genie-ACS...) options... but it seems to me that's oriented more to "collecting configurations" than "managing" especially some HA (paired) setups.
Correct me if I'm wrong... or even better, suggest some "actual" solution.

Thanks!

Regards,
 
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Re: VRRP sync-connection-tracking setup

Fri Sep 03, 2021 1:14 pm

Yeah... I know about the "possibilities" or "options" for centralized management...
but are there any "suggested"/Recommended "product/solution" for that purpose?

I know about for ex Unimus and some other similar products and the TR-69 (Genie-ACS...) options... but it seems to me that's oriented more to "collecting configurations" than "managing" especially some HA (paired) setups.
Correct me if I'm wrong... or even better, suggest some "actual" solution.

Thanks!

Regards,
Hi guys,

Any news/suggestions on the topic?

Is there a recommended way to sync the router's configurations?

Thanks!
Daniel
 
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raimondsp
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Re: VRRP sync-connection-tracking setup

Fri Sep 03, 2021 6:26 pm

Hi,

The entire team is focused 100% on stabilizing v7.1. Let's get back to this topic after v7.1 stable release.
 
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Re: VRRP sync-connection-tracking setup

Fri Sep 03, 2021 6:44 pm

Nice... someone is actually *reading this*...

Great! I really hope the 7.1 will hit "production" soon and that config sync will follow soon...

Mikrotik "clusters" would be *FANTASTIC* after all this years and a requirement for "enterprise" deployments.

Keep the good work you guys!

Best regards
M.C
 
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Re: VRRP sync-connection-tracking setup

Tue Oct 05, 2021 5:41 pm

Is it possible to sync connection tracking state in an active/active setup?
I like to peer via BGP with my upstream provider, so i like to have two active bgp sessions and so on to route the traffic from WAN to LAN where the traffic arrives. So there is a possibility of asymmetric routing. Because of that, syncing the connection tracking tables is important.
 
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raimondsp
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Re: VRRP sync-connection-tracking setup

Thu Oct 07, 2021 1:53 pm

Is it possible to sync connection tracking state in an active/active setup?
I like to peer via BGP with my upstream provider, so i like to have two active bgp sessions and so on to route the traffic from WAN to LAN where the traffic arrives. So there is a possibility of asymmetric routing. Because of that, syncing the connection tracking tables is important.
We are considering decoupling sync connection tracking from VRRP, and make connection syncing a standalone feature that users may set up in any way they want. However, I wouldn't expect this feature soon because the developers are fully focused on stabilizing v7.1, and there is a growing list of features to be developed after v7.1 stable. Meanwhile, you can create a "fake VRRP interface" that is used for nothing but syncing connections in the opposite way.
 
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Re: VRRP sync-connection-tracking setup

Wed Dec 08, 2021 11:57 am

Nice... someone is actually *reading this*...

Great! I really hope the 7.1 will hit "production" soon and that config sync will follow soon...

Mikrotik "clusters" would be *FANTASTIC* after all this years and a requirement for "enterprise" deployments.

Keep the good work you guys!

Best regards
M.C
1000% agree with above statement. Been waiting for this feature for years. At this moment in time I have to use products from competitors. Once Mikrotik does this, no more need for the products from competitors.
 
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Re: VRRP sync-connection-tracking setup

Thu Jan 27, 2022 10:45 pm

We are considering decoupling sync connection tracking from VRRP, and make connection syncing a standalone feature that users may set up in any way they want.
This sounds greate.

But i have an another question:
While R1 is VRRP Master and CONNTRACK Master, should i see the connections on the BACKUP-Router R2 under IP > Firewall > Connections?

Because currently i do not.

Running v7.2rc2.

Currently i can only see the connection tracked on master, but not on slave?
side-by-side.jpg
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Re: VRRP sync-connection-tracking setup

Fri Jan 28, 2022 8:58 am

If sync-connection-tracking is set and running, you should be able to see the connections on the backup router (no counters, though). Make sure you have the same Firewall rules set on both ends. Also, forcing connection tracking might help:
/ip/firewall/connection/tracking/set enabled=yes
 
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Re: VRRP sync-connection-tracking setup

Fri Jan 28, 2022 11:53 am

Okay, i beleave that there is no initial sync? I am right?
For my point of view only new connections will be synchronized to the Backup-Router?

EDIT: And if there was a SIP-Connection this information is not synchronized between Master <> Backup Router. When a new session will be established at port 5060, master syncs the tracking to the backup, but is loosing the SIP-Conntrack-Type. The UDP message is only alive for 30 secs after creation on the backup router when it is 1h alive on the master.

If i reboot the Backup-Router, the whole connection tracking table is empty. But when new connections are made, the connection appears on the backup router.

After 8 hours, both routers are not in sync. I do not think, that this is a configuration issue. I think there is a initial sync missing.

By the way: will it come to a point, where connection-tracking-syncing is able to handle active/active sync? So we can make use of the potential power of two routers instead of one doing the hard work and the another is sleeping all day long?

Form a software engineers view: Doing some MQTT / Message Broker Stuff on Mikrotik to exchange the connection-tracking informations, when initially connected to the broker and when new connections gets established and when a connection will die because of reached timeout. In this setup you will be able to handle more than just two routers for connection tracking.

This is my related firewall and vrrp configuration:
[rack@ROBEL-VoIP-Gateway-RZ1] > /ip/firewall/export
# jan/28/2022 10:43:35 by RouterOS 7.2rc1
# software id = QWJ1-SK2Q
#
# model = RB5009UG+S+
# serial number = EC190FA9F86B
/ip firewall nat
    add action=src-nat chain=srcnat out-interface=ether1.Uplink-RSM to-addresses=185.58.31.141
/ip firewall service-port
    set sip sip-direct-media=no
/interface vrrp
    add interface=ether2.Uplink-Core-Switch name=vrrp.voip-router preemption-mode=no priority=50 remote-address=10.1.160.3 sync-connection-tracking=yes vrid=88
/ip address
    add address=10.1.160.2/24 interface=ether2.Uplink-Core-Switch network=10.1.160.0
    add address=10.1.160.1/24 interface=vrrp.voip-router network=10.1.160.0
    add address=185.58.31.141/28 interface=ether1.Uplink-RSM network=185.58.31.128
    add address=172.16.18.3/29 interface=ether1.Uplink-RSM network=172.16.18.0

[rack@ROBEL-VoIP-Gateway-RZ2] > /ip/firewall/export
# jan/28/2022 10:44:00 by RouterOS 7.2rc1
# software id = SEY8-DGED
#
# model = RB5009UG+S+
# serial number = EC190FC52FD2
/ip firewall nat
    add action=src-nat chain=srcnat out-interface=ether1.Uplink-RSM to-addresses=185.58.31.141
/ip firewall service-port
    set sip sip-direct-media=no
/interface vrrp
    add interface=ether2.Uplink-Core-Switch name=vrrp.voip-router preemption-mode=no remote-address=10.1.160.2 sync-connection-tracking=yes vrid=88
/ip address
    add address=185.58.31.141/28 interface=ether1.Uplink-RSM network=185.58.31.128
    add address=10.1.160.3/24 interface=ether2.Uplink-Core-Switch network=10.1.160.0
    add address=10.1.160.1/24 interface=vrrp.voip-router network=10.1.160.0
    add address=172.16.18.4/29 interface=ether1.Uplink-RSM network=172.16.18.0
 
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Re: VRRP sync-connection-tracking setup

Wed Feb 02, 2022 4:49 pm

Also i see the following information in log after Reboot (marked interesting log entity with >>>>):
currently running 7.2rc3 on both routers.
 14:46:15 system,info router rebooted
 14:46:15 vrrp,info vrrp.voip-router now BACKUP
 14:46:15 vrrp,info vrrp.voip-router starting CONNTRACK SLAVE
 >>>> 14:46:15 vrrp,warning NFCT_SLAVE: could not open NETLINK socket (93) - Protocol not supported
 14:46:16 interface,info sfp-sfpplus1.qv-rz2 link up (speed 1G, full duplex)
 14:46:19 interface,info ether1.Uplink-RSM link up (speed 1G, full duplex)
 14:46:19 interface,info ether2.Uplink-Core-Switch link up (speed 1G, full duplex)
 14:46:20 vrrp,info vrrp.voip-router starting CONNTRACK SLAVE
 14:46:22 system,info,account user rack logged in from 185.58.28.171 via winbox
 15:48:08 system,info,account user rack logged in from 185.58.28.171 via local
 
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Re: VRRP sync-connection-tracking setup

Wed Feb 02, 2022 5:15 pm

IP address on VRRP interface must have /32 netmask if address configured on VRRP is from the same subnet as on router's any other interface.

In your case, it should be:
/ip/address add address=10.1.160.1/32 interface=vrrp.voip-router

Regarding the NETLINK socket error, did you force connection tracking (change from the default "auto" to "yes")?
/ip/firewall/connection/tracking/set enabled=yes
 
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Re: VRRP sync-connection-tracking setup

Thu Feb 10, 2022 7:02 pm

(change from the default "auto" to "yes")?
After changing both to routers to yes, the message is gone, but there is no initial sync after booting R2 (Backup).

 16:58:00 system,info router rebooted
 16:58:10 vrrp,info vrrp.voip-router now BACKUP
 16:58:10 vrrp,info vrrp.voip-router starting CONNTRACK SLAVE
 16:58:10 vrrp,warning UDP send error (101) - Network unreachable
 16:58:10 interface,info sfp-sfpplus1.qv-rz2 link up (speed 1G, full duplex)
 16:58:11 vrrp,warning UDP send error (101) - Network unreachable
 16:58:12 vrrp,warning UDP send error (101) - Network unreachable
 16:58:13 vrrp,warning UDP send error (101) - Network unreachable
 16:58:13 vrrp,warning UDP send error (101) - Network unreachable
 16:58:13 interface,info ether1.Uplink-RSM link up (speed 1G, full duplex)
 16:58:13 interface,info ether2.Uplink-Core-Switch link up (speed 1G, full duplex)
 16:58:15 vrrp,info vrrp.voip-router stop CONNTRACK
 16:58:15 vrrp,info vrrp.voip-router starting CONNTRACK SLAVE
 16:58:16 system,info,account user rack logged in from 185.58.28.171 via winbox
 18:00:10 system,info,account user rack logged in from 185.58.28.171 via local
Screenshot 2022-02-10 180205.jpg
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raimondsp
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Re: VRRP sync-connection-tracking setup

Mon Feb 14, 2022 4:43 pm

We were unable to reproduce your issue. On our side, initial sync gets performed as intended.

Please create a support ticket, so we can reproduce exactly the same setup as yours.
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 03, 2023 10:16 am

Yeah i will send you the support-ticket as far as i can.

But i have a related question: Is it possible that the Slave dont have the synced connections in his own conntrack-table?

Our setup looks like this:
Download.png
Green = Upstrem to the Internet - works
Blue = Downstream from the Internet - works
Orange = Downstream from the Internet via R2 - do not work - R2 discards packets

We looked to the FIREWALL > CONNECTIONS Table and saw correct UDP and TCP connections. We did some Tests with UDP Echo-Server and sent a packet from PC to Internet to get new entry in connection tracking. When we routed the traffic via R1, the echoserver was functional. But as we sent the traffic via R2, packets reached the server but the answers were discarded on R2.

This looks like, the conntrack-table is only in memory and not active on R2.

When marking R1 as Slave and R2 as Active, the UDP-Echo-Server was full functional when we sent traffic via R2. But as we switched traffic to R1, the Echo-Server stopped working.

Active-Active is possible with linux conntrackd userspace client without any issues:
https://conntrack-tools.netfilter.org/m ... ml#sync-aa
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raimondsp
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Re: VRRP sync-connection-tracking setup

Fri Feb 03, 2023 2:23 pm

Currently, RouterOS supports only Active-Backup setups. Active-Active is not supported.
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 03, 2023 2:46 pm

Active-Active is possible with linux conntrackd userspace client without any issues: https://conntrack-tools.netfilter.org/m ... ml#sync-aa

Just curious, is this the Mellanox extension (MAGP) or a completely separate linux implementation with similar functionality?
 
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Re: VRRP sync-connection-tracking setup

Sat Feb 04, 2023 3:26 pm

is this the Mellanox extension (MAGP) or a completely separate linux implementation with similar functionality?
Conntrackd is only a daemon that inter-exchange flow-based connection tracking to one or more routers via multicast protocol. With that technique you are able to setup a active/active/active/active NAT-Router.

Yes this is a Unix/BSD/Linux thing, but is a standard-library and nothing special.

With OSPF and ECMP you can split traffic with Layer3+4 rules between all available gateways. Each flow is fixed to one nat-gateway, but when one gateway fails, traffic can switch to another NAT-Gateway.

The NAT *n Gateway have always the same IP-Address on the LAN and WAN interface or even better on the loopback-interface.
 
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Re: VRRP sync-connection-tracking setup

Thu Feb 23, 2023 5:52 pm

Hi.
should I set the synchronization on each VRRP interface or is it enough on one?
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 24, 2023 5:18 am

both
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 24, 2023 11:22 am

Hi.
should I set the synchronization on each VRRP interface or is it enough on one?

Hi,
You need to set sync-connection-tracking=yes only on one VRRP interface (on both ends). If multiple VRRP interfaces are grouped together, enable sync on the group-master.
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 24, 2023 1:22 pm

If multiple VRRP interfaces are grouped together, enable sync on the group-master.
can u elaborate more on this please
 
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Re: VRRP sync-connection-tracking setup

Fri Feb 24, 2023 1:26 pm

Check group-master description in MikroTik VRRP documentation
 
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Re: VRRP sync-connection-tracking setup

Sat Feb 25, 2023 4:47 am

You need to set sync-connection-tracking=yes only on one VRRP interface (on both ends). If multiple VRRP interfaces are grouped together, enable sync on the group-master.

So only sync-connection-tracking=yes on group-master. Other VRRP in the group dont need to
 
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Re: VRRP sync-connection-tracking setup

Mon Feb 27, 2023 10:10 am

You need to set sync-connection-tracking=yes only on one VRRP interface (on both ends). If multiple VRRP interfaces are grouped together, enable sync on the group-master.

So only sync-connection-tracking=yes on group-master. Other VRRP in the group dont need to
exactly
 
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Re: VRRP sync-connection-tracking setup

Fri Mar 03, 2023 10:35 am

is there any option to synchronize dhcp leases like sessions in contrack ?
 
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Re: VRRP sync-connection-tracking setup

Fri Mar 03, 2023 4:52 pm

Just to make sure that I've understood this thread correctly - I have two RB5009s with VLANs in VRRP configuration. I've enabled pre-emptive mode for all the VRRP interfaces, set one of the VLAN VRRPs as the Group Master, and then enabled Sync.Connection Tracking on the Group Master interface on both routers. Is this is indeed allowed and correct according to what I have read?

The reason I ask is that as I conduct fail over tests by removing the trunk cable from my primary router, I am able to cycle once or twice before I then see a vrrp warning message in my log that says: CTSYNC link down. At this point, the backup router never transitions from master to backup nor does my primary take over as master. It's almost as if the sync communication between the two routers dies. If I disable the Sync. Connection Tracking on the backup router, this issue seems never to occur and I am able to fail over back and forth many times with no issues. Happy to post configs but wanted to see if anyone else (or Mikrotik staff) had observed the same issue.
 
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Re: VRRP sync-connection-tracking setup

Mon Mar 06, 2023 9:49 am

Just to make sure that I've understood this thread correctly - I have two RB5009s with VLANs in VRRP configuration. I've enabled pre-emptive mode for all the VRRP interfaces, set one of the VLAN VRRPs as the Group Master, and then enabled Sync.Connection Tracking on the Group Master interface on both routers. Is this is indeed allowed and correct according to what I have read?
Yes, that's correct.

Just to make sure that I've understood this thread correThe reason I ask is that as I conduct fail over tests by removing the trunk cable from my primary router, I am able to cycle once or twice before I then see a vrrp warning message in my log that says: CTSYNC link down. At this point, the backup router never transitions from master to backup nor does my primary take over as master. It's almost as if the sync communication between the two routers dies. If I disable the Sync. Connection Tracking on the backup router, this issue seems never to occur and I am able to fail over back and forth many times with no issues. Happy to post configs but wanted to see if anyone else (or Mikrotik staff) had observed the same issue.
I'd like to see the network diagram to ensure we are on the same page.

Please remember that disconnecting the physical cable (LINK DOWN) transitions VRRP into the FAILURE (F) state because it can no longer serve as VRRP master (no link) nor as a backup (no CTSYNC connection). VRRP is a Layer 3 redundancy protocol. There are different mechanisms for redundancy on lower layers, such as MLAG.

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