Hot answers tagged trunk
11
Usually overly large ethernet frames can be and are discarded. In the presence of things like jumbo sized frames large ethernet frames are hard to define, so it really depends - but discarding will be probably the most frequent behavior encountered.
edit:
To elaborate: Standard IEEE 802.3 Ethernet frame size is 1518 bytes, 802.3Q adds 4 bytes to the frame ...
9
I have actually seen this on a cheapo-switch. Someone had connected a switch between a trunk port which had a couple vlans. The frames were forwarded with the vlan tagging intact. The other ports on that switch where able to use the un-tagged vlan.
A switch only needs the source/destination mac to decide which ports to forward the frames to, so this ...
4
You haven't provided any info about the interfaces you're going to use with the fibre link, so I'm guessing that this is 1gbit.
If the switches you're going to use have 1gbit copper interfaces aswell then it's no problem to trunk between them, this is the normal way of connecting switches that have several uplinks.
I need to warn you however - if those ...
4
What you propose will work, but is not ideal from a redundancy perspective.
You propose this:
A better topology that would allow for link or core switch failure would be this (note it only uses two fiber ports in the core, but you have a building-to-building link). Obviously spanning tree of some sort must be enabled on all switches to prevent loops:
If ...
4
Based on the product brief for the NetXtreme card, it looks like there's support for up to 64 defined VLANs. Configuration is done via the Advanced Control Suite (on page 35). Fundamentally, 802.1q support is implemented before the network traffic gets to the OS. I've been using 802.1q trunks since the Windows 2000 Server days.
4
You need to ensure you have a HDMI v1.3 or 1.4 compliant cable to achieve this, even then you'll never see more than 8.16Gbps due to overhead.
I've never seen HDMI being used this way, most sysadmins just buy switches with 10Gig ethernet ports to deal with the...erm, 10Gig ethernet. I like the ideal of the HDMI but it sounds a bit fragile a solution (as is ...
4
The consumer-class switch will attempt to forward the frame -destination MAC address is all it cares about. If the destination MAC address is not in its CAM table, it will flood the frame out of all its ports, except the one the packet was received from.
A switch that uses Cut Through forwarding method will definitely forward the frame, since it begins ...
4
Spillover can approximate failover by setting the Egress Bandwidth on the fast connection to a value much greater than its maximum bandwidth.
Assuming wan1 is the fast connection, adding wan1 followed by wan2 to the user configured trunk means that when both connections are up, wan2 will never see any traffic because the bandwidth will never exceed wan1's ...
3
Best thing to start with is setting up a Trunk Port on one of the four last Ethernet ports, as you will need to Tag all our VLANs out to the next switch. could be best to buy the same vendor (DLINK) as i've had to do a few firmware upgrades on DLINK's myself to get them to properly tag packets for and trunk
It also sounds like you want to setup an ...
3
Start simple and iterate.
Trunk them together with single GigE. If you've got ~20 workstations and printers in a typical office, you're probably not hitting GigE wire speed at this point anyway.
Next step is to do GigE link aggregation (802.3ad). Try 2 GigE connections between each switch, or maybe 4. If your traffic is pretty evenly spread over your ...
3
The following lines on the spec-sheet are the interesting ones:
IEEE 802.1Q Static VLAN (256 groups, Static) -- Supports VLANs
IEEE802.3ad Link Aggregation (manual or LACP) -- Supports trunking
Since you only have a single LAN port on your server, trunking probably won't do anything for you. You can feed multiple VLANs to a single port.
3
You need to use the 'ip route 0.0.0.0 0.0.0.0 192.168.1.1' command like you mentioned instead of the existing 'ip default-gateway' command. 'IP route' commands work for all traffic while 'ip default-gateway' is only for traffic originated by that switch.
Also unless whatever is attached to Gi0/2 is a switch configured to trunk you don't want Gi0/2 to be a ...
3
Before reading the rest
Unfortunately, I don't have enough reputation on the SO-site to ask questions so I've made a lot of rough assumptions in the below answer. Please, please, please elaborate and ask questions before taking action on anything below.
The software version
The revision isn't the only important piece of information - the "train", or ...
2
Intra-VLAN Routing
In your first question, your correct in your first assumption that users in VLAN 0 won’t be able to contact users in VLAN 2, to include the l3-interface you have set up on SW3, but only because you haven’t set up a default-gateway on PC2 or SW3.
What is the next thing a host does if it sends out a broadcast on its VLAN and receives ...
2
There is a redundant path in the network as the loop between SW3 and SW6 is closed.There is no broadcast storm in the network? What is the reason for this?
Spanning Tree Protocol
2
The important parts of your log are these two WARNING messages:
[2012-08-01 09:08:11] WARNING[3921] chan_sip.c: Retransmission timeout reached on transmission 3e57de11239b49f10930969c7e23d1ca@50.58.42.81:5060 for seqno 102 (Critical Request) -- See https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions
Packet timed out after 9983ms with no response
...
2
Get a networking specialist to do it. Seriously.
In modern networks, trunking generally refers to the idea of passing multiple VLANs from one switch to another, not teaming switch ports for more bandwidth, which probably won't help anyway. Get a faster switch, get faster NICs on the server sending out this HD video, get QoS in place, get... well, a ...
2
OK I just had this happen between an older PiaF (1.4) box and a new one running asterisk 1.6.
Turns out newer asterisk has added some security features that need to be turned off to be intercompatible. It actually turned out the messages were in the asterisk log file, though I wasted 2 hours before seeing them:
[2011-01-18 02:39:01] ERROR[15257] ...
2
LACP is the Link Aggregation Control Protocol. It is all about setting up link aggregation automatically and dynamically whenever more than one link is available and the other side speaks LACP as well. It typically is used with redundant server-switch interconnection since a static setup with link aggregation would break server connectivity as long as the ...
2
The issue was this was found to be that by default Spanning-tree was enabled on the 2848 Layer2.
If I plugged another branded switch into the Layer 3 6248 and then the other switch into the 2848 it would work.
Going from the Dell to Dell would not work at all. Turning off STP on the 2848 solved this issue.
I have also found that using "spanning-tree ...
1
It looks like your D-Link switches support link aggregation, so I would use that to increase the amount of uplink bandwidth, using a star configuration.
Something like this:
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What you're saying re: "trunking" the switches together, assigning ports to VLANs, etc, is basically sound. I wouldn't be using 10GbE in such a small network. If you need more than 1Gb bandwidth between the switches you might consider using link aggregation, which should still be rather cheaper than 10GbE ports.
The "HDMI" connections you're seeing to stack ...
1
your switch is in vtp client mode, which means you cannot edit the vlan configuration on that switch. if you have setup vtp for the three switches then you'll want to make the changes on the vtp server switch. for such a small implementation, though, you should really put all three in vtp transparent mode (which will enable you to edit each switch ...
1
Do you want the host to have access to just vlan 37 or do you want the host to have access to multiple vlans?
This IOS configuration means set the native (that's untagged) vlan to 37.
interface GigabitEthernet 0/1
switchport mode access
switchport access vlan 37
On the linux side, the vconfig command creates an interface alias for traffic tagged ...
1
As user97408 points out, you should change the mode of the backup interface to Passive. If you only have one Active interface, the load balancing algorithm selection doesn't really matter. (Screenshot Edit WAN_TRUNK)
I have also enabled Connectivity Check in the settings of each wan Ethernet interface, as in my setup the ZyWall is unlikely to see link loss ...
1
Depends on the equipment. I'm assuming that you're using Cisco gear, from their treatment of 1002-1005? Some of their stuff can drop those vlans from the allow list, some cannot.
As long as you don't want the traffic for those vlans going over the link, then there's certainly no reason to allow them. The fastest way to find out whether you equipment ...
1
I imagine what you're hoping to do is to use two physical interfaces on the 5510, with each interface connected to one of the switches, and then both interfaces are joined together in software to act as a single logical interface. Cisco refers to this as EtherChannel; on servers it's often called bonding. Unfortunately, according to ...
1
Interesting question with a few possible answers but first an important question.
Why do you want to do this?
iSCSI performance will be terrible, the latency will likely cause timeouts on the SCSI bus and transfer speed will be low.
The easiest way to do this would be to configure the ASA to have a subinterface on vlan 2 and simply route the traffic, ...
1
HP use 802.1q not ISL
I presume that you are using two physical ports on the ASA.
Please confirm what device connects with which port to what device for all devices, or create a simple diagram.
As a blind guess, I would presume that you have the tagged and untagged ports incorrectly assigned. On a HP switch, everything is on VLAN 1 unless changed.
If you ...
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