Archive for September 2014
If it wasn’t Twitter I probably would not have known there was a CWNP conference going on, but luckily we have Twitter. Looks like it was a 3-day conference about all things wireless, I really will try and go next year.
It also looks like they posted the presentations on their website found here, I’ve looked through almost all of the presentations at this point and there are definitely some good ones in there. I hope they take a page from CiscoLive365 and post videos of the actual presentations in the future. Even if there is a small fee they would be worth it (or maybe be available certified CWNP’s?). While you can read through some of the presentations and get some valuable information from them, there are one or two that would probably offer much more insight if you could see/hear the presentation.
I really like Jerome Henry’s presentation on WLAN ‘range’, because believe it or not there are still quite a few people out there that say ‘This AP can cover 1500 sq. ft’, sure maybe it can but what will data rate be and will clients transmission be able to make it back to the AP when they start approaching the edge of the wireless cell?
Jonathan Linton’s VoWLAN, is another good one going over some best practices and design considerations.
There is also a good one on Transmit Beamforming, now I don’t want to re-type the entire page up so go check it out!
Recently PVLANs came into a design discussion, which in turn led into me reminiscing on my Route/Switch days. So naturally when I wanted to re-visit the topic if anything to make sure I still remembered everything what was important and to see if any features have been added with the new IOS’s. It’s been a while since my last PVLAN deployment so here we go!
- Promiscuous Port – This is the ‘primary’ VLAN that can communicate with all the other Isolated & Community ports with the PVLAN environment.
- Isolated Port – This is a ‘secondary’ VLAN that will only communicate with the ‘primary’ promiscuous VLAN. Isolated ports cannot even communicate with other isolated ports. Since we are talking about VLANs, communication is blocked at the Layer 2 perspective. (At which layer do VLANs operate at, Layer 2)
- Community Port – This is another type of a ‘secondary’ VLAN, like Isolated ports a community port can also communicate with the ‘primary’ promiscuous VLAN. The big difference here is that a port configured in a ‘secondary’ community VLAN can also communicate with other ports configured as community ports. They will not however be able to communicate with ports configured in an ‘isolated’ VLAN.
Since these Private VLANs operate at layer 2 it is worth pointing out some specific traffic flows, after all it is worth considering the implication of this isolation and typical broadcast/multicast flows:
- Broadcast Traffic
- The promiscuous port will forward broadcast traffic to all isolated & community ports. (Including trunks)
- The Isolated port will only forward the broadcast to a promiscuous port. (Including trunks)
- Community ports will forward broadcast to the promiscuous & other community ports. (Including trunks)
Configuration & Topology:
- The configuration is not too bad, you’ll notice the first thing we do is set the VTP to transparent mode. If you are running VTP v1 or v2 this needs to be done.
- Next we create a VLAN like normal, however under the vlan configuration, we set the PVLAN mode. Here we are setting VLAN 888 to be a ‘primary’ promiscuous VLAN.
- Next we create VLAN 871, and designate it as a ‘secondary’ isolated VLAN
- Followed by us creating VLAN 861, and marking is as a ‘secondary’ community VLAN.
- Once we finished creating our ‘primary’ & ‘secondary’ VLANs we need to associate our ‘secondary VLANs’ to our ‘primary’ VLAN.
To re-cap, we set the VTP mode to transparent, created and assigned out promiscuous VLAN along with creating and associated our isolated & community VLANs, not too bad right?
Now that our VLANs are defined lets map these Layer2 private VLANs to a Layer-3 SVI:
So there, we created the SVI for VLAN 888 (The primary VLAN) and we associated the ‘secondary’ VLANs to the SVI with the private-vlan mapping add command. You’ll also notice the system message stating that our mapping was successful.
Now, that we have Layer-3 mapping lets go ahead and assigned a few ports to our private VLANs.
Here we, enter interface fa1/0/20, set the switchport mode to private-vlan host and configure port 20 to be an isolated port. (By placing this port in the isolated PVLAN)
Port fa1/0/21 on the other hand is configured to be in the ‘community’ VLAN.
Next, we are going to configure Port Fa1/0/22 to be a promiscuous so it can communicate with ports in both VLAN 861 & 871:
Verifying the PLVLAN configuration is simple enough:
show int private-vlan mapping – Verify your Layer2 to Layer3 mappings
show int switchport – Verify Layer2 switchport parameters
show vlan private-vlan – Verify PVLAN setttings & ports.
I know I’ve been quiet of my blog this month, but that’s not because I’ve forgetting about this site! For the month of September I’m spending some extra time over at Thwack, this is SolarWinds community where everyone likes to get together and talk about network management. I’ve talked about Network Management quite a bit on this blog in broad topics, and during September at Thwack I get focus on VoIP Network Management.
That announcement aside, the Thwack community is great! I’ve been member of the community for many years (Unfortunately under a few different accounts until I nailed one down a single account). Especially if you are SolarWinds user here are a few highlights of the community:
- Content Exchange – There is a good chance if you are looking for a particular report or custom poller someone else may have already thought about it to, and there also a chance that it might be available in the context exchange available to be downloaded an imported into your SolarWinds platform.
- Feature Request – Got an idea that will make a SolarWinds product easier or better enter this section, the more users that agree with your idea the better a chance it may get implemented into the system
- Feel free to ‘+1’ my request for better & more stream lined monitoring of F5 Virtual Server 🙂
- Great discussions & news updates from SolarWinds – There are many forums on Thwack that focus on different areas of network and systems management, with many great discussions going on. SolarWinds is also great at keeping their users in the know in regards to updates and possible upcoming features.
So far my posts have been about the following:
- How do you prepare for a VoIP deployment? What items are on your VoIP readiness checklist.
- I also took some extra time to consolidate many of the great recommendations into a single document found here.
- What tools do you use to troubleshoot VoIP related issues?
Come join the discussions!