Routing

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!

Hi,

What version vMX that u used? I suggest u use gigaethernet not ether-option because it for vEX.

Thanks

Original Message:
Sent: 07-19-2025 16:21
From: Mostafa Nabil
Subject: issue with vMX acting as RR

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!

------------------------------
Mostafa Nabil
------------------------------

Hi,

What version vMX that u used? I suggest u use gigaethernet not ether-option because it for vEX.

Thanks

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!

Did you configured ? 

set chassis aggregated-devices ethernet device-count <*> 

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!

Did you configured ? 

set chassis aggregated-devices ethernet device-count <*> 

Hey everyone,

I'm working on a Juniper MX150 (vMX) router, which is acting as a secondary Route Reflector (RR). The other side of the RR is an ACX5448.

Initially, I tried to bundle two 10G links using LACP to form an AE interface. However, I discovered that vMX doesn't support LACP, and the configuration is ignored with this warning:
run show configuration interfaces xe-0/0/13
##
## Warning: configuration block ignored: unsupported platform (vmx)
##
ether-options {
    802.3ad ae1;

As a workaround, I configured two separate /30 point-to-point interfaces (one for each physical link).

The issue I'm now facing is that BGP sessions are flapping frequently, even on the primary RR, when both P2P links are up.

I suspect the problem may be related to per-packet load balancing, which I'm currently using:

set policy-options policy-statement per_flow_load_balancing then load-balance per-packet
set routing-options forwarding-table export per_flow_load_balancing

If anyone has experienced a similar issue or has suggestions on how to stabilize the setup (e.g., better load balancing strategy or routing tweaks), I'd really appreciate your input.

Thanks!