Cisco :: How A Bandwidth Gets Distributed In Switches
Nov 20, 2012
I have got a very basic/fundamental doubt.I would like to know how a bandwidth gets distributed in switches.for example consider a scenario where i have a coreswitch A and coreswitch B connected between each other througha a 1Giga Fiber now each of my core switche are connected to two edge switches through fiber links. all edge switches have giga ports. now if i connect a pc with giga link in th edge switch of coreswitch A and tansfer a file to a PC connnected to the edge switch in network B.how does the switch allocate/distribute bandwidth?
I just purchased a Dlink DSL-2750U today which I am using with my ADSL connection. I have three wired computers using this connection and no wireless systems at the moment. I would like to know if it's possible to share the bandwidth evenly amongst these three computers? The other two computers are hogging on the bandwidth leaving me with barely anything to work with.
We would like to install a pair of ACS 5.4 apliance as primary /backup in our two datacentres.I have some question regarding degin.
1- We have 800+ network device to monitor , can we install by range of address instead of instlling one by one in device host database ? 2- Do We have to install all 800 device first on Primary and then again on backup or Primary will replicate to backup server? 3- We do not have real IP address yet, so if we built with dummy address and make them pair and all the database sync, then when we change their IP address, will the distributed primary pair will have any issue with backup ACS server?
I was wondering if the following scenario would work:
2 Microsoft TMG servers (could be any W2K8 R2 based server, e.g. UAG, Exchange etc.) configured for Unicast NLB. The servers are connected to separate L2 switches which are connected to a highly available central L3 switch (see attached drawing).
Unicast NLB works in such a way that it uses a shared virtual IP and a virtual MAC addres which is not used as Source MAC address when the TMG servers are respondign to requests.Basically it relies onto the fact that the switch does not learn the virtual MAC address and floods all packets destined to the virtual MAC on all ports. The L3 switch would learn the MAC through ARP. The question now is, what the L3 switch would do, if it receives a packet destined for the NLB VIP. It should do an ARP request in order to receive the virtual MAC. How would he decide on which port(s) to forward the packet as he does not know on which port the MAC is found. Can he make a decision based on Layer 3 (IP/VLAN based) therefore he knows that the VLAN for the TMGs is connected on those two uplink ports?
I was looking to 6500 series switches. I saw DFC4 module (WS-F6K-DFC4-A, WS-F6K-DFC4-AXL) and (WS-F6K-DFC4-E, WS-F6K-DFC4-EXL). Data sheet for supervisor engine 2T wrote that for maximum performance you should DFC4. I'm a bit confused. I didn't any useful information about it:
1. DFC4 is a separate module(consumes 1 slot)? Does it have any ports on it?
2. Is it a daughter card? If yes, should it be installed on supervisor or it should be installed on line cards?
I am struggling in some areas to work out my firewall rules for a distributed deployment. The referenced documentation is not entirely clear in my opinion. In some instances it is easy to work out what ports need to be opened eg Admin node TCP 22,80,443 for management from administrator hosts/ranges. In other instances it difficult to work out eg TCP 1521 Database listener and AQ is this for ISE nodes only or for access devices aswell
My question is whether there is a better document that details these requirements. What rules are meant to be ISE node - ISE node communications and which rules are for access device - ISE, or ISE - access device. One of the rules I am pretty confused about is the PSN CoA ports. SHould the rule be WLC - PSN on 1700 and 3799 or is it the otherway round or unidirectional?
I am pretty sure that the ports are meant to be ISE-ISE in most instances barring the PSN for Radius and CoA.
I have a SG 300-20 small business switch and I would like to restrict bandwidth by gateway ip address but not by physical port or LAG. On the web interface, I can only do bw limiting per port or lag. I want to do bandwidth limiting by the IP addresses that I assign to vlans that my hosts use as a gateway ip.
Just put in an SF302-08P switch with two AP541N's. Just a Comcast modem connects into the switch along with the two WAPs, nothing else. Speedtest through the cable modem with nothing plugged into it is 48Mbps. Then connecting a single laptop via the switch shows a speedtest of 33Mbps. Then with the two AP541N's plugged in and using the same laptop over WiFi, I'd consistently seen 10Mbps for downloading. But going right back to the cable modem directly showed me close to 50Mbps in a speed test.
Have factory defaults in all the Cisco devices, and poured over the settings and it looks like bandwidth limiting is disabled. Suspecting maybe it is for QoS and to optimize voice, but I see definite places in the devices where I could designate optimizing voice and those aren't enabled. Then started thinking with tweaking the wireless frequencies, but didn't want to do anything too unstable.
Does the SGE2000 supports NetFlow? I've checked the Cisco docs and also called Cisco support to which no one has been able to answer me.
Anyhow, just in case it doesn't support NetFlow, how to be able to set up something that would be able to check the bandwidth usage on each port?
I've got a problem where I think the SGE2000 switch is failing when I pump around 190~200Mbps through x2 of the ports (Server A on port 1=130Mbps and Server B on port 2=60Mbps) of Multicast traffic (UDP). I can measure the output from the Streaming servers that provide the multicast content, thats how I know the input to the switch and I know that there are no packets lost or any errors departing from the servers, yet when I increase server B to say 80Mbps, I get break up and all sorts of problems on the client end STBs and it is happening on the multicast content provided by Server A too which is a different source, so I'm 99.9% sure its a SGE2000 switch problem which is why I'd like to monitor it somehow.
would like to know how a bandwidth gets distributed in switches.for example consider a scenariowhere i have a coreswitch A and coreswitch B connected between each other througha a 1Giga Fiber, now each of my core switche are connected to two edge switches through fiber links. all edge switches have giga ports. now if i connect a pc with giga link in th edge switch of coreswitch A and tansfer a file to a PC connnected to the edge switch in network B.. how much bandwidth would i get?how does the switch allocate bandwidth?
I have a cisco Swtich SGH 300-20 Gigabit switch i configure 2 vlan one is default and one is vlan 10
Vlan 1 ip range 172.16.0.0/23 Vlan 10 ip range 172.16.2.0/24
Client on Vlan getting Proper IP from DHCP Server all i need is to distribute internet bandwidth we have 6/3 mb and i want to give 4/2 mb to vlan 1 and 2/1 mb to Vlan 10
Int Gi16 on switch is configured as trunk port and is connected to cisco 2811 router
what are the command used to distribute bandwidth between these 2 vlans
I am using using 2 broadband with tp-link dual wan router 10 pc using the broadband.does any one know about the router who controls bandwith there is option available in Tp-Link Dual wan router but its not working...is there any router which automatically takes bandwith and allow as per my details.
I'd like to use an SG200 swicth to allocate bandwidth on a 100 Mbps fiber Internet uplink.I will have 5 routers (each supporting a separate network) connected to the SG200, and I'd like to give each network 20 Mbps. QOS configuration, best CIR and CBS settings for this.
We have 1 mpbs bandwidth line, but most of the time we are getting only 300-500 kpbs download speed, i want to send statistics report to our ISP, what will be best procedure to test the bandwidth report, i have checked in some websites like bandwidthplace and speedtest but these sites are not accurate, how to check the actual bandwidth we getting from ISP against 1 Mbps. We have solarwinds monitoring tool in this i have configured the WAN interface for 1 mbps
If I have two stackable switches one switch uplinks to one 6509 core switch and the other connection uplinks to another 6509 core switch, and also the other stackable switch does not connect to the core switches. Because I am using hsrp and also we are not using vss then one uplink to the core is not in used only ones is so then how does creating an etherchannel between does two uplinks to both core switches benefit me in anyway such as more bandwith and using both uplinks at the same time or I'm I wrong?
Vlan 10 is the management VLAN, and it uplinks to our border router.Vlan 20 is the workstation VLAN, and all workstations point to the switch as their default GW? Vlan 30 is the ip phone VLAN, and all phones use this as their gateway.
I would like to put a LAG between said switches, we have some servers on the ip phone switch that need to be accessed by the workstation clients, and the single 100mb link through the router is probably not going to be enough.As I understand it, because the switches have different networks on them, a simple lag will not work. I did create a lag, and assign ip addresses to each side, however in that mode, it doesn't appear I can block vlan 10 from transiting the LAG, and with out that block I will end up with a logical loop, and spanning-tree will block one of the uplinks, or the LAG itself.
If I have two stackable switches were only one stackable switch has two uplinks one uplink goes to one core 6509 switch and the other uplink goes to the other 6509 core switch can a Layer 3 etherchannel be used if each uplink go to a different core switch, by the way hsrp is running between both switches and also can you give an example how data will be routed from the stackable switch through the ethernetchannel to one of the core switch accross the WAN to another core switch?
I have a stack of 6 switches and I want to add another over the gbit connector using fiber. I already connected but I can acces the network from the new switch. I don't have any issues on my Stack all resources are available Do I need to do some special setup or connection to enable this? Can be stacked like the others? I already usen the 2 stacking port can i Add another switch?
we just received 5 new SF200-48 Smart Switches for small business. I noticed only way I can configure them is by using the web gui. Is there a way to enable good old CLI?
now we have 2 switches: SF300-24..on one SF300-24 we config it at layer 3 mode with VLAN configuration same as following [code] And we use port 26 on 2 switches SF300-24 is trunk mode then we connect both SF300-24 switches.But on SF300-24 layer 2 cann't inderstand VLAN from Sf300-24 layer 3..How to config VLAN on 2 switches SF300-24 Layer 3 and SF300-24 layer 2?
I was looking for configuring QOS for two VLANS i have created. these will be for voice traffic vlan 22 and video traffic vlan23. i also have three other vlans for pc's, wireless devices and our cnc machines. we have 5 switches that are all SG30028P's with a single switch doing the intervlan routing (operating at layer 3). all of the switches are trunked back to the main switch and ive been through the guide written on how to do this on a single switch which i dont think is layer 3.
I'm replacing 2 3COM 4500 Swithes with the SG300-52 Cisco switch. We have 3 VLANs, 10, 20, 100. The switch is set for Layer 3 and I have setup DHCP relay. what settings i should set on the Cisco for the following setups:
I'm setting up an SNMP poller to retrieve the ARP table (ipNetToMediaPhysAddress) from my SF300 switches. I can retrieve the table from SF300-24P and SF300-48P switches running Firmware Version 1.0.0.27, but get garbage for the MAC address when retrieving that same table on the same model switches running Firmware Version 1.1.1.8. Is there an outstanding defect on this code level? How can I retrieve the table showing the IP address to MAC address mappings?
We have several of the SG300 Serices switches. We use them to route VLAN traffic to Remote Offices, Internet Connections, and WiFi Access Points.In one remote office we have a SG300-10 setup to route the HQ Network and the remote Office Subnet. The SG300 is Connected to HQ via Fiber and has multiple Tagged VLANs on it. If I do speed tests over the Fiber Link on the Incoming Tagged Netwotk I get Decent performance, 80Mbs. If I switch to a networtk that is not priginating from HQ, and have the SG300-10 route packet, I get dismal performance. 15-20Mbs.
I Fireded up a New SG300-28P FW v1.2.7.76. Added a the HQ VLAN 101 and new VLAN 1025 . Mapped some Tagged and untagged ports for each. Switch was connected to HQ Network as untagged VLAN 101. I put a laptop on an Untagged VLAN 101 port. Ran some tests, cam back with 750-850Mbs. Great. Put the same laptop on a Tagged 101 Port, Configured the NIC for Tagged VLAN 101, Same test, same Speeds, 750-850Mbs.I then Configured laptop for Tagged VLAN 1025. Connected to tagged VLAN 1025 port. Ran speed tests, resuts were 15-20Mbs!
I then Configured laptop for Untagged VLAN 1025. Connected to unagged VLAN 1025 port. Ran speed tests, resuts were 15-20Mbs!It was only the Laptop and the Connection to the HQ net on the SG300-28P. Why is the performance of this unit soooooo poor when it needs to route?Other Switches have FW v1.0.0.27 or FW v1.1.2.0. They have Similar speed issues. All Configured for Layer 3.
does the SG300 switches can be used with Microsoft NLB in Multicast mode?I know on traditional Catalyst switches you can statically "map" IP's to mac's and then to multiple ports but this doesn't seem to work correctly on the SG switches - it gives an error about the mac not being not Unicast?
We have a project in which we are using 34 Cisco SG200-18's each with a MGBLX1 (LC Single Mode Fiber) SFP mini-GBIC.All the fiber's come back to one building where we must "bridge" all 34 fiber connections. What hardware should be used to accomplish this? A L2 switch? For example, a 12 port SFP Switch with Fiber SFP's accepting the first 12 fiber connections, then other switch with SFP for the next 12 and so on, until there is a overall capacity of 36 and having patch cables between the 3 switches?
what cisco or non cisco hardware would work with these SF200-18's to accomplish this?
Any snmpset commands to add, modify and delete vlan table entries on SG300-10 switches? I checked url... however this information is apparently only valid for catalysts. The latest firmware is installed and the provided MIB files are used.
I looking to buy SGE 2010 swith, but I have some question:
1. Can I use 4 SFP ports and stack of two switches at the same time. 2. Is it possible to use for stacking ports other than 24, 48? 3. What is maximum possible number of ports to use for stacking (can I get more than 1Gb thruput).
I'm going to have several SG300-28P switches to setup. I'll need to create multiple vlans for data, voice, and wireless traffic. I have the following questions in setting up this configuration:
1) For managing the switches via IP, will LAN1 be the default management network? Should I create a seperate VLAN for managing the switches?
2) For uplinking the switches together, I plan to trunk a port to connect the switches together. What's the configuration on the trunk port to forward all vlans from one switch to another?
3) On some ports, I want to configure a trunk for two vlans (Data and Voice) where the phone has a pass through for PC. The phone supports tagging for the PC and the VoIP traffic. For example on port 10, would VLAN 100 and 300 be set to tagged?
We had a SGE-2010, just purchased 2 (two) SGE-2010P. I want to stack the switches (all 3) (unless there is a better way). Not sure what is needed hardware wise, and how to physically wire the switches. Had switches years ago (diff brand) that used a special cable that connected the switches. It seems that is not the case here. I have not used fiber in networking before so I am new to that part, I’m willing to learn, just need pointed in the right direction.Can all three switches be stacked, (1) SGE-2010 & (2) SGE-2010P? I THINK I need to use the GBIC port 4 to stack, I understand 1 port is enough if two switches are used, but what about three or more switches.What are the other GBIC ports used for? Will I be better off (can I ) use the GBIC ports LAG (2 ports) to the other switches? Or would regular ports work just as well?
