Windows 2008 Server R2 NAT problems with VLANs
My Windows 2008 server R2 has two NICs. First NIC is connected to my ISP (IP assigned with DHCP). Second NIC is dedicated to LAN communication and is connected to HP ProCurve switch “trunk” port with multiple VLANs (Vlan7 and Vlan8). Configuration of these card are: First NIC: All settings are from DHCP. (ISPs NIC) Seconf NIC (Local Area connections): -LAN7: 192.168.7.1 Mask: 255.255.255.0 Gateway: blank -LAN8: 192.168.8.1 Mask: 255.255.255.0 Gateway: blank (Pings from VLAN7 [...]
Continue Reading »Understanding Native VLANs
As I understand it (and that is questionable): This pertains to Cisco equipment. 1-Switch traffic on a port, configured in access mode with a static VLAN, is tagged with a VLAN field before being sent out the trunk port? 2-Control traffic is untagged. Untagged frames are “tagged” with the PVID of the Native VLAN? 3-The purpose of trunking is to allow multiple VLAN traffic across the same link? 4-The native VLAN is for legacy or [...]
Continue Reading »Multiple ports on same LAN segment
I’m trying to set up a RouterBoard right now, but I don’t think this question is specific to RouterBoard. I have 4 ports all of which need to be on a certain subnet, we will say 192.168.2.0/24. However, one of the four ports must carry this plus another bit of traffic. This RouterBoard does not allow me to do a “switch group” unfortunately, and that was my first thought. Adding these ports to a “switch [...]
Continue Reading »Can’t understand how VLAN Tagging, Untagging Works
I’m trying to setup a 48 ports gigabit switch (netgear GS748T). My goal is to split the 48 ports to 3 vlans : VLAN10 ports 2-20 VLAN20 ports 21-30 VLAN30 ports 31-46 What i did is : On VLAN1, TAG port 1, UNTAG every other ports On VLAN10, TAG PORTS 2-20, UNTAG every other ports On VLAN20, TAG PORTS 21-30, UNTAG every other ports On VLAN30, TAG PORTS 31-46, UNTAG every other ports I didn’t [...]
Continue Reading »For VLANs: difference between untagged and non-member setting for ports?
The “default” VLAN is VLAN 1, and traffic over ports are Untagged by default (at least, in the switches that we use). We’ve created VLAN 2 and marked the necessary ports as Tagged, and it’s working beautifully. However, all of the ports that I did not Tag are blank/non-members by default. What is the difference between having a port Untagged vs. being a non-member for the VLAN? Asked by Bigbio2002 If a port is a [...]
Continue Reading »Device vlanVID does not seem to be present error when starting vlan interface
EDIT#2: I think I found the cause of the issue: in /proc/net/vlan/config there is an old entry for vlan620 which links to bond0 (I was trying to do bonding originally) plus an old vlan620 file again tied to bond0. How can these entries be removed since contents of /proc cannot be edited like normal files? I am trying to use eth0 as 802.1q trunk interface – my configs are as follows: ifcfg-eth0 # Intel Corporation [...]
Continue Reading »Offshore application development – Access to dev network (Security best practice)
Let me start by telling you that I’m not very technical, but need to provide someone with some guidance and I was hoping you could assist. The situation is: – Dev and Prod subnets (Not sure if they’re in different VLANS, but on diff subnets) – Current in-house developers apparently need access to both prod and dev networks, so completely segregating them may not be an option – They now also need to provide access [...]
Continue Reading »Separate virtual switches or just VLAN separation for isolated networks?
I am building a small setup of ESX5 servers. There will be different apps running for different companies on them. Each company has a VM that has one Internet facing vNIC and one vNIC facing to this company’s private virtual network (backend). The backend networks are for separate web server and database VMs. The question is: would it be performance and/or security wise better to create a separate virtual switch for each company or just [...]
Continue Reading »Traffic blocked between VLANs despite security-level difference on ASA 5510
I have an Cisco ASA 5510 configured thus: interface Ethernet0/0 description ### Trunk for inside, wlan ### speed 1000 no nameif no security-level no ip addressinterface Ethernet0/0.10 description ### OFFICE ### vlan 10 nameif inside security-level 100 ip address 172.18.0.1 255.255.255.0 interface Ethernet0/0.12 description ### WIRELESS ### vlan 12 nameif wlan security-level 20 ip address 172.18.2.1 255.255.255.128 interface Ethernet0/3 description ### Upstream ### nameif outside security-level 0 ip address X.X.X.X 255.255.255.252 access-group WLAN in interface [...]
Continue Reading »Wireless Guest Network VLAN
I’m currently in the process of setting up some D-Link DAP-2553 WiFi access points. They have the ability to broadcast multiple SSIDs. These SSIDs can be assigned to VLANS (which I am pretty new to). I would like to have an internal network (which I assume will be VLAN1) and a guest network (like VLAN2). What I would like to do is to have the internal network have access to the “network” so they can [...]
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