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8 votes
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Two switches, double connection, no LACP: how does it work?

Most likely, the rapid or the multiple spanning tree protocol RSTP/MSTP has been activated on the 1910 switch. With the unmanaged 1410 switch forwarding STP BPDUs (most do), the 1910 notices a loop to ...
Zac67's user avatar
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7 votes

Two switches, double connection, no LACP: how does it work?

Most switches comes with Spanning Tree (STP) enabled by default. This protocols will detect the loop and disable one of the link to break it. The new switch you connect either has STP disabled or a ...
JFL's user avatar
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6 votes
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LACP and how to configure switches correctly

Your ethernet SFP/SFP+ for fiber are going to be 1 or 10 Gbps. There isn't a 2 Gbps ethernet fiber SFP (some vendors used to count this way because of full duplex, but it is still 1 Gbps in each ...
Ron Maupin's user avatar
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6 votes

Best way to connect VLANs / STP / LAG

VLANs are a way of partitioning a given network into distinct layer 2 segments as if you'd be using separate switches, so you don't have your whole network bunched together. The advantage of VLANs ...
Zac67's user avatar
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6 votes
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Network Redundancy with LACP Trunking

Scenario A: Switch 1 has ports 1+2 trunked together via LACP. They are plugged into Switch 2 ports 1+2. Both links will be used, but a single flow will only use one link. There is a hashing ...
Ron Maupin's user avatar
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6 votes

Capturing LACP PDUs in an aggregated link on Juniper MX

show lacp interfaces <aeX> displays detailed state information for each member-link in a LAG. For example: user@router> show lacp interfaces ae0 extensive LACP state: Role Exp Def ...
Jeff Wheeler's user avatar
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5 votes
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LACP: Between RB750 and Huawei Ne20

Not sure what you tested. You need to aware that any single flow will only use one of the port combinations each way. Port aggregation allows you to increase the throughput for multiple flows, not for ...
Zac67's user avatar
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5 votes
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Bridge Assurance with vPC on port type network

Spanning-tree port type network activates bridge assurance on the link. Since the 2960X doesn't support bridge assurance, you can't run this link as port type network. Just run it in normal mode. ...
Rooster's user avatar
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5 votes
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Can I use 802.1x and LACP to secure the networking infrastructure?

802.1x was specifically designed for end-point devices to authenticate to network switches and was not designed for switch-to-switch connections. Because of this, it is highly unlikely that you will ...
halfmetaljacket's user avatar
5 votes
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LACP Huawei S6720

Static LAG trunks are just that: static. When multiple interfaces are connected they are regarded as a single logical port. LACP trunks are negotiated by protocol. That way you can ensure that they ...
Zac67's user avatar
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5 votes

Layer3 vs Layer2 LACP

The choice between using a L2 or L3 link is really independent of LACP. Assuming your LACP hashing algorithm choice uses layer 3 information to choose the link (and your ISP does the same), there is ...
Ron Trunk's user avatar
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5 votes
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what will change in a trunk between lacp mode and trunk mode?

LACP is a protocol where both side negotiate the trunk - if either side doesn't use LACP both (all) links will stay separate. STP may step in and prevent a bridge loop. A static trunk uses no ...
Zac67's user avatar
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5 votes
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Can LACP connect to 2 different firewalls?

Can LACP be set up to connect to two different firewalls? If LSW-1 and LSW-2 are indeed multi chassis LACP capable (Stack, Stackwise, M-LAG, multichassis LACP, VPC, VSS ... feature names vary by ...
Marc 'netztier' Luethi's user avatar
4 votes
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Server link bond across 2 switches with LACP, inter-switch LAG dropping alternate pings?

This problem happens because Linux bonding in 802.3ad mode sets all slave interfaces to the same hardware mac address ("borrowed" from the first enslaved interface). Then LACP PDUs are transmitted ...
Teodor Milkov's user avatar
4 votes
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LACP to Fix Switch Bottleneck?

The setup is totally valid, provided all devices support LACP LAG. Two things though: The network design is not very good, neither for reliability nor from the performance/efficiency perspective. ...
Zac67's user avatar
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4 votes

Network Redundancy with LACP Trunking

From a functional point of view, there's no difference between LACP trunks and static trunks. All links are aggregated (with the limitations Ron has already pointed out) and the aggregation group is ...
Zac67's user avatar
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4 votes

Inconsistent behavior of link aggregation

It depends on the LACP load balancing algorithm. The LACP load balancing algorithm is only locally significant (they don't have to match on Mellanox and Arista switch). Load balancing algorithms are ...
OlofL's user avatar
  • 108
4 votes

Can LACP connect to 2 different firewalls?

Generally, LACP does not support grouping links from multiple chassis. LACP works between two entities, not more. However, there are proprietary stacking solutions that combine multiple physical ...
Zac67's user avatar
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3 votes

What is the difference between 'clock synchronization' and 'time synchronization'?

At least in the context of network devices clock synchronization tends to refer to synchronous circuits where a constant time signal has to be maintained so that two devices can know the precise rate ...
rnxrx's user avatar
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3 votes
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show mac address on aggregated interface - Junos

The MUCH easier way to do this is via LLDP - this will show you each interface that is part of the LACP bundle and which port it attaches to on the remote switch. If you don't/can't/won't enable LLDP ...
Benjamin Dale's user avatar
3 votes

LACP balanced VPN: Bad or good idea?

The basic problem with this, and every other aggregation scenario, is how you will accomplish the load sharing. By that I mean, how will the host determine which link to use to forward the packet out ...
Ron Trunk's user avatar
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3 votes

LACP rate slow vs fast... impact on bandwidth?

For ISSU on Cisco NX-OS to work you need run LACP configured as "SLOW" and you still detect any issues with the port-channel!
Jeffry's user avatar
  • 31
3 votes
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Adding a switch to provide redundancy

Do you have enough router ports available to do this ? You would still have your five trunks between the two buildings, but an outage on SW1 wouldn't bring down the whole LAN anymore. You would need ...
tonton gerrit's user avatar
3 votes

Spine and Leaf architecture with LACP

Do we have the same active-atcive link aggregation between the leaf and the server? From the diagram, you've got a single link to each server. Of course, you can also use LACP LAG, static LAG, or ...
Zac67's user avatar
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3 votes
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Can I aggregate multiple uplink ports between Ethernet switches?

Goal: To the greatest extent possible, I would like to provide 10-GbE line-rate performance between any pair of hosts in both rooms. In order to truly guarantee 10G, you'll need 10G dedicated ...
Zac67's user avatar
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3 votes

using 802.1x with nic teaming

LACP and 802.1X don't mix. Unless there are vendor-specific extensions allowing that(?) you can't use them simultaneously on a port. Link aggregation is normally used between switches or towards ...
Zac67's user avatar
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3 votes
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How to capture mixture of packets with and without VLAN tag over LACP with tcpdump?

The -e flag doesn't work this way. When you write tcpdump .... -e vlan it doesn't mean "show vlan tag if available". It means "show link-level header" and "show only packets ...
Mikko Rantalainen's user avatar
3 votes
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802.11s Operations

No, laptops and other supplicants do not act as repeaters/extenders. Yes, commercial-grade wireless access points with mesh capabilities will generally also support wired links. Most consumer-grade ...
Jeff Wheeler's user avatar
  • 5,469

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