Cisco Switching/Routing :: LACP Fast Updates On 3750s?
Sep 5, 2012
I've got LACP-enabled port-channels between a Cisco 3750 stack and a few different switches (some Cisco 3750s and some Juniper EX2200s). The Ciscos are all sending slow LACP updates, the Junipers are sending fast LACP updates (but the Cisco they connect with is responding with slow LACP updates).
I have a couple of questions:
1) what are the pros and cons of slow vs fast updates? my research has led me to the conclusion that fast updates are better for network resiliency as long as you have plenty of bandwidth overhead (which I do at the moment). is there anything to add to this conclusion?
2) is there any way to configure the Cisco 3750s for fast updates?
I am running the latest version of 12.2(55)SE6 on the catalyst and I am looking for this command "lacp rate fast" but it is not there:
lab-c3750#conf t Enter configuration commands, one per line. End with CNTL/Z. lab-c3750(config)#interface g1/0/5 lab-c3750(config-if)#lacp ? port-priority LACP priority on this interface lab-c3750(config-if)#lacp
According to this link, it is supposed to work: [URL]Am I missing something?
If we have 3 stacked 3750s# running Layer 3. Do we need license for every switch? or is it one license for the 3 switches? Also is the license associated with the MAC address of a specific switch? What i# am trying to know also, is if we have to install one license and it is associated# with one MAC and this switch failed.. will the Layer 3 be broken?
We've recently inherited a platform with little handover and also minimal networking experience.We're going 100 miles an hour in learning, but I'm a bit confused with the idea of a L2 switch with no IP assignments to ports, so using VLANs, and a L3 switch with IP assignments. And the combination of both.We have 2 Cisco 3750 switches, along with a whole host of other hardware, so we're starting at this "gateway" to start breaking things down.
I've read the document (Document ID: 91672) on setting up WoL, but I had a few questions as this doesn't completely fit our situation.We have 4 3560 switches, 3 have only access to vlan 1, SW4 has access to vlan 1 and vlan 2, every switch is connected by fiber to a 3750.We want to enable every server/PC on vlan 2 to allow WoL packets to all PC's on the internal network (so WoL through all 5 switches). In the above document, it allows WoL to be executed only from a single IP/Server, is it possible to allow an entire vlan to execute WoL? or allow multiple IP's to execute WoL? Also, in the switch configuration it says to type
I've to enable it on 3750 and nexus 7K switches. what are the steps involved? can we enable jumbo frame per port instead of enabling globally? i.e. we will only have few ports that will be using jumbo frames, rest of the ports will be using default 1500 MTU size.
Here's what I'm trying to do. We are having new storage servers installed that will be using NFS. I'm being told that they need to have their connections port channeled. Right now, the servers have connections to 2 different 3750s for HA. Is it possible to configure a port channel between these 2 connections?
can you stack a 3750 switch over fiber.....the answer is no, but the virtual switching supervisor 720-10G for the 6500 can create one virtual switch using two 6500s...
how can we get cisco to come up with a way for access switches to be stacked over fiber similar to above supervisor? i know of few of my site that would benefit from this...maybe they can come up with a vss appliance, similar to a media converter, to convert stackwise over fiber...then of course, you would need the same appliance on the other end....
I have a network with static routes witch I need to convert to OSPF.Never used OSPF, and do not have much experience in routing in general.The netvork is connected via some fiber links, but moastly wireless bridges.I have attached a drawing of how the network is.Routers are 3550, 3560 and 3750s.Each router is on a different physical site.
We're trying to configure our Cisco 4507 (Supervisor Engine IV) to allow a new Dell server with a pair of Broadcom 5708 GigE NIC's to aggregate its NIC's to give us a 2gbps link to the switch.
So far we seem to have got the team and LACP up and enabled, but the adaptor that the Broadcom Admin Util creates for the team is only showing a 1gbps connection where I would have expected it to show as 2gbps.
The individual NICs show as connected at 1gbps. We're not Cisco experts so are struggling on how to get the 2 NICs to aggregate.
On the server side we've done nothing other than create a team using 802.3ad LINk Aggregation using LACP.
This is what I think the relevent output from "sho conf" is, more available if needed.
version 12.2 boot system flash bootflash:cat4000-i9s-mz.122-18.EW1.bin ! interface Port-channel2
i'm desperately trying to get LACP working over a dot1q Tunnel. The "Service Provider" Switches are two 4506-E Switches with SUP7-E connected via a 10G Link, running on cat4500e-universalk9.SPA.03.03.00.SG.151-1.SG
dot1q tag vlan native interface GigabitEthernet3/1 switchport access vlan 2001
I am trying to configure a 6509 as the passive receiver from a Dell Force10 10Ge switch with 2 sfp to 2 gig ports on our 6509 switch, I see LACP is up on both sides but cannot pass traffic, I have only 2 vlans that will carry across the aggregate link from our vmware boxes, this is just a temp until I get a 10ge in our 6509 chassis.
I have two N5K (5020) switches with NX-OS - 5.0(3)N2(1). These two switches form VPC domain: peer-link = 2*10Gb ports (1/17-18) and peer-keepalive link over managements ports.Also I have two HP servers with two 10 Gb ports on each server.Each server conected by one link to each N5K switch (1/9-10). N5K downlinks configured as access ports with LACP Active mode.There is only one VLAN (1).When "no shut" command entered on N5K access ports - ports going in "not connected" status, begin flap and then going in "linkFlapErrDisabled" state.In attach - "sh run" from N5K.
We have 2x WS-C3560X-48 with the 10Gb SFP C3KX-NM-10G module.I want to use the 10Gb SFP (with a redundant 1Gb link) between each of the switches.Below is the configuration what I think I should use. Is this correct?
SWITCH1 int TE1/1 switchport trunk encapsulation dot1q switchport mode trunk channel-group 1 mode active
We also want to utilise Link Agrrigation for the servers that attach to the switch. Would this config be correct?
port-channel load-balance src-ip int range x switchport mode access switchport access vlan 1 (They are all on the default vlan) spanning-tree portfast channel-group x mode active
(Then I would configure the LACP config on the server) Is there anything I am missing?
I need to implement LACP HP servers mostly DL 380 g7 with Intel based dual port with two types of Cisco equipment first scenario server connected to 3750x stack of 4 switch's .second scenario same server type connected to two Cisco Nexsus 5596 . My question regarding two type of connection.Is it possible to do active active ?Would it give fault tolerance ?With HP LACP implementation is there known issue or should i expect latency with such configuration?What is the maximal lag- channel group that is possible per type?
I have an 1841 running Advanced Enterprise Services 12.4(22)T3 that is functioning as a DHCP server and DNS server. What I am trying to figure out how to do is have the DNS service respond to queries about the clients of the dhcp service. I have successfully enabled it as a caching server for other requests, like "google.com" and "cisco.com", but what about the hosts on the local LAN?
As an example, let's say a Windows computer connects to the network with the hostname "computer" and receives an IP address from the 1841 with the domain name "test.net". I would like the 1841 to serve DNS queries for "computer.test.net" with the IP address that it assigned.
I am trying to get a 1811 to update routes on a 3750x. My static routes are being redistributed to the switch fine, however my connected networks are not My router has Vlan with several subnets attached.
interface Vlan1 description $ETH-SW-LAUNCH$$INTF-INFO-FE 2$$ES_LAN$$FW_INSIDE$ ip address xxx.xx.xx7.185 255.255.255.0 secondary ip address 188.8.131.52 255.255.255.0 secondary ip address 184.108.40.206 255.255.255.0 secondary ip address 10.170.10.254 255.255.255.0 secondary
A host on the xxx.xx.xx6.0 network cannot ping a host on the 10.10.44.0 network. All ports on the switch and the router are in vlan1
If after having an active peer-link port-channel between a couple of nexus 7010 I change lacp system-priority on both boxes and then I add a new member interface on that port-channel , that interface will be aligned with new lacp system-priority value but the old member do not and so I have to reload those modules which include old member interface.
We are planning to have attach topology with nexus 5548 using vpc. Let me know if this i possible. I want to configure dual NIC linux server using LACP active mode to connect to two 5548 in VPC for redudancy as well as use of full access layer bandwidth. On nexus this will be access port in single port channel in single VPC link.
I have a Cisco 6513 switches connected to HP VC Flex 10 Module. The (2) 10Gb ports on a Cisco Switch connected to VC Flex-10 in LACP mode.
I need to move those (2) 10Gb ports on Cisco Switch 10Gb Module to a different 10Gb module on a same Switch without bringing the ports down since it is a live environment.
What I would do is to configure a same port channel ID on a new 10Gb module and then move port one by one. unplug one port and connect to the new port on a module. While I will be unplugging the first port the other active port will keep sending traffic and as soon as I plug in on another port, both ports will be active.
We have several DMVPN-connected sites that are connected to our 2821 ISR pair.They're all configured as eigrp stub connected summary. Yesterday, a few of the sites went inaccessible, but the VPN tunnels were still up and running. Upon further investigation, we noticed that the remote sites stopped receiving routing updates from our 2821's. As a quick fix, we added static routes to bring the sites back up.Later that night, we removed the static routes and cleared the eigrp neighbors, hoping it would fix the problem. When it didn't, we cleared them two more times.Suddenly, the router lost all downstream adjacencies. While we were adding statics to at least bring the sites back up, all of the adjacencies came back.
I have configured a portchannel with 3 ports - lacp active mode I want to pxe boot esx server with Hp Proliant DL 360 G7.
During Pxe Boot the physical Interfaces must be in (I) state - standalone.
The server receives via dhcp the ip but after getting the ip the link goes down for a short time and the switchport goes down and then in (w) state - waiting to be aggregated. Now the server tries to load via tftp the image but the server gets a timeout because the switchport is in state (w). It takes a long time til the switchport comes back in standalone mode (I).
Is it possible to modify the time how long the switchport is in the waiting to be aggregated state on 3750x ?
Would the right command be lacp rate-fast? But this command is not available on 3750x, only 6000 series.
I am having an issue on a Cisco 3750 stack where when the stack master is rebooted, all my lacp port-channels drop and then come back up again. After doing some investigation It seems that it is happening because of lacp using the stack master mac-address as part of the system-id, so when the stack master reboots, the stack mac changes. I see that there is the command: stack-mac persistent timer 0
There is this warning about using this command:
When you configure this feature, a warning message displays the consequences of your configuration. You should use this feature cautiously. Using the old master MAC address elsewhere in the domain could result in lost traffic.
My question are:
Are there any other consequences to using this command (apart from moving the switch/mac to another location in the network)It mentions 'If the entire switch stack reloads, it acquires the MAC address of the master as the stack MAC address' Is this still the case if you have the stack-mac persistent timer to 0? Does using channel-group mode on for the port-channels still use the same mechanism of having a system-id? (Will the channels flap using 'mode on' when rebooting the stack master.
We have Dell M6220 blade server that server is connected to cisco 3750 switch. I am trying to configure LACP in 3750 for two port which are connected to Dell M6220 server switch. The channel-group 2 mode active commande is not taking then its showing the error protocol mismatch and if i run show int port-channel 2 command the port channel status is showing down. The Dell server switch is on simple mode. below i have attached the required details.
Switch#show int port-channel 2 Port-channel2 is down, line protocol is down (notconnect) Hardware is EtherChannel, address is 0000.0000.0000 (bia 0000.0000.0000) MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set