5 votes
Accepted

Switch to Server Connectivity

Without further information, the encircled links indicate channel bonding/trunking. Bonded channels (or LAG trunks, Etherchannel) are regarded as a single, logical link. STP doesn't block any of the ...
Zac67's user avatar
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4 votes
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Help optimize a LAG with LACP and two different algorithms on each side

We don't have router, all we have L2 switch network. We have many servers behind trunk, so should i use src-dsp-ip? or src-dst-mac ? You need to weigh several factors to determine which method to ...
Ron Maupin's user avatar
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3 votes
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EtherChannel ports standalone after restarting packet tracer

You cannot connect a layer-3 channel to a layer-2 trunk channel because the layer-3 channel can only process the native VLAN unless you create subinterfaces for it. Remember that a layer-3 interface ...
Ron Maupin's user avatar
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3 votes

How to trunk VLANs over Layer 3 EtherChannel?

L3 EtherChannel and VLAN/Trunk concepts DO NOT work together. In this scenario, you should use L2 EtherChannel between L3-1 and L3-2 switches. Ensure that you create all L3 Int VLANs / L2 VLANs, ...
Hung Tran's user avatar
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3 votes
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Is a port channel necessary between redundant core switches?

Would a port channel be necessary between C1 and C2? Not always. The point is to provide sufficient bandwidth between the cores plus you don't want that link to fail. Why would we want to configure ...
Zac67's user avatar
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2 votes
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Is there no "mode on" for channel-group in GNS3?

The problem was existing because I was not using ether switch module ports that is added to router to handle it as switch
Ahmad Z. Tibi's user avatar
2 votes
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questions about link aggregation

Up to eight ports in a channel group. Up to eight ports in a channel group. Yes you can (see below); it's an interface. It depends on the switch model (see below). For #3: Interface Commands (show ...
Ron Maupin's user avatar
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2 votes
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Is test etherchannel load-balance disruptive?

Not so far as I am aware. All it does is simulate sending data and seeing which interface would actually be carrying the packets. Granted this is to the best of my knowledge and I might be incorrect....
Zack Scaringello's user avatar
2 votes
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Etherchannel Basics

Q1: The primary device in the VPC pair is the only device in the VPC pair that can send, receive or respond to BPDUs. As such the secondary device will only forward them along to their destination. ...
Zack Scaringello's user avatar
2 votes
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Guidelines for network design of bladecenter

That's how I run most of my VMware systems. The main issue with mixing traffic and management is anything that disrupts that physical interface will also kill your management access. (STP blocking, ...
Ricky's user avatar
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2 votes
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Link Aggregation (Etherchannel) between 2 cisco switches ( fibre link, and with an intermediate switch)

Q1: This requires MLAG (multichassis LACP) to work. You can't split and splice a simple static or LACP trunk. Q2: As far as I know, SG500X and SG300 don't support MLAG. You can configure a LAG trunk ...
Zac67's user avatar
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2 votes

Need clarification on some Cisco configurations

There's no such thing as "switchport mode acces vlan 1, 2, 3" A switchport in access mode will be associated with a unique VLAN and the packet leaving the port will be untagged. (Well, if you use a ...
JFL's user avatar
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2 votes

Interface suspended when linking access to core

Hi I haven't got a reputation score of 50 yet so can't add to the comments... But following on from what @Cown was saying here are the guidelines from Cisco: All ports must be identical: - Same speed ...
ssedwards's user avatar
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2 votes
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mLACP or vPC on L3 interfaces

(m)LACP and vPC are Layer 2 technologies, thus they don't apply to layer 3 interfaces At layer 3 you use for example VRRP (to provide gateway to hosts) or routing protocols (like OSPF) to achieve ...
JFL's user avatar
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2 votes
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Add links to a port channel group without downtime

Short answer: no. While the STP handover in step 4 or step 3 is usually faster than 1 second there's always a gap. Make sure you're using RSTP, MSTP or RPVST though. The original and largely obsolete ...
Zac67's user avatar
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2 votes
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Sharing VTP Info Between two VTP Servers

OK. You have a couple of problems. First, you need to make sure that the channel is a trunk. VTP only works on trunks. On both switches: interface Port-channel1 switchport mode trunk ! Next, you ...
Ron Maupin's user avatar
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2 votes
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Etherchannel physical port SPAN mirror

That is what I've found: Can You Configure SPAN on an EtherChannel Port? An EtherChannel does not form if one of the ports in the bundle is a SPAN destination port. If you try to configure SPAN in ...
reybanger's user avatar
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2 votes

Is it possible to limit the number of active links in a channel group?

That's not possible with PAgP. Traffic is always aggregated across the whole LAG trunk. Splitting the trunk in two groups of two ports plus spanning tree would work (switching over to the spare trunk ...
Zac67's user avatar
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2 votes
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Two channels between two switches

Depending on your actual goal, there are several possibilities. Load balancing your flows 'at will' requires them to be split across different VLANs or very delicate fine tuning. VLANs with spanning ...
Zac67's user avatar
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2 votes
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Etherchannel configuration on two differents routers and 1 L3 switch

No. All the channel members on one end of the channel must be on the same device. If you are looking for a single IP address in the switch, you could do that on an SVI and connect layer-2 switch ...
Ron Maupin's user avatar
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1 vote

test etherchannel load-balance command doesn't work

That command is not available on those models.
Ron Trunk's user avatar
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1 vote

How would I configure etherchannel for this particular topology?

Since all "education, certification, or homework" questions are off-topic here, we will not give you the answer (and you don't include enough information for that, anyway), but below is enough ...
Ron Maupin's user avatar
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1 vote
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L3 Etherchannel cost calculation

You didn't tag this with a vendor, but you use the Cisco term, "portchannel," so I assume you mean this as a Cisco question. Q1: I have read that in layer 2, if any of the links of a portchannel ...
Ron Maupin's user avatar
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1 vote
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Cisco 2960 etherchannel suspended mode

This often happens when you connect to an interface that doesn't have LACP enabled, as you have discovered. Using CDP or LLDP will tell you for sure what the interface on the other end is, assuming ...
Ron Maupin's user avatar
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1 vote
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Etherchannel configuration!

If I understand you correctly, you have four bridges in a loop, but you want to load balance. The problem is that STP will block one direction in order to prevent layer-2 looping. An etherchannel ...
Ron Maupin's user avatar
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1 vote

mLACP or vPC on L3 interfaces

Yes, you can absolutely. You can setup a Port-Channel interface and set it with an IP. This is referred to as a Layer 3 port-channel and you can run routing protocols over it as needed. This will ...
HostBits's user avatar
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