Hello, while configuring the MLAG configuration on two CRS326-24S+2Q+ switches, I encountered incomprehensible behavior that could potentially lead to a service failure during operation. I have attached a physical connection diagram (png) and updated to the latest version of the ROS7 branch.
To connect the server, I use SFP-DAC-001 cables.
The first problem is that when disconnecting the network adapter on the server, the status of the sfp plus interface remains active. At the same time, if I disable the interface from the switch side, then it will be in the disconnected status on the server (network cable is not connected)
The second problem is that the bonding used as the basis for MLAG uses the state of the physical link (Mii monitoring) to determine the state of the logical LACP channel (802.3ad), which leads to packet losses as soon as I disable the interface from the server side.
It is very strange that the physical state of the link is used to check the state of the logical LACP channel, while the physical link may be active but not configured on the other side and this will also lead to packet loss.
At the same time, when I disconnect the interface from the server side, despite the fact that the physical link on the switch remains active, as well as the bonding interface attached to it, the failure indicator may be the lack of LACP negotiation. At the same time, this field is visible in winbox (bonding interface - status - lacp partner system id) and it becomes empty as soon as the agreement is violated.
For what reason can I not select this field as the activity of the bonding interface?
I wrote to technical support on this issue (SUP-114652), but maybe there will be some thoughts here. I recently set up exactly the same configuration on arista switches (but 1g ethernet). They can clearly separate the stages: after connecting the cable and after agreeing on the LACP protocol, as well as configure different VLAN settings
To connect the server, I use SFP-DAC-001 cables.
The first problem is that when disconnecting the network adapter on the server, the status of the sfp plus interface remains active. At the same time, if I disable the interface from the switch side, then it will be in the disconnected status on the server (network cable is not connected)
The second problem is that the bonding used as the basis for MLAG uses the state of the physical link (Mii monitoring) to determine the state of the logical LACP channel (802.3ad), which leads to packet losses as soon as I disable the interface from the server side.
It is very strange that the physical state of the link is used to check the state of the logical LACP channel, while the physical link may be active but not configured on the other side and this will also lead to packet loss.
At the same time, when I disconnect the interface from the server side, despite the fact that the physical link on the switch remains active, as well as the bonding interface attached to it, the failure indicator may be the lack of LACP negotiation. At the same time, this field is visible in winbox (bonding interface - status - lacp partner system id) and it becomes empty as soon as the agreement is violated.
For what reason can I not select this field as the activity of the bonding interface?
I wrote to technical support on this issue (SUP-114652), but maybe there will be some thoughts here. I recently set up exactly the same configuration on arista switches (but 1g ethernet). They can clearly separate the stages: after connecting the cable and after agreeing on the LACP protocol, as well as configure different VLAN settings
Statistics: Posted by mark99i — Fri Feb 16, 2024 2:43 am