vlans on Rhel5

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We have vlans configured on our switches and was told by Red Hat support  that it is recommended to configure Vlans on Rhel using vconfig 8021q module. Anyone have vlans setup on RHEL 5.  Is thier any benefit?. Been using Rhel5 without them for some time now and everything seems ok. . I dont know anyone who is using them.

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We use 802.1q VLANs extensively. It's an easy way to have a very flexible network configuration.

Hi Tony,

 

if you have the need to separate logical networks on the same physical network, VLANs come in handy. I've also seen them being used as a security improvement, but that is more security by obscurity to be honest.

 

Cheers

 

Marko

First of all  you need to assess whether you need VLAN configuration for your network or not.

 

If you need to segregate different network, want enhanced security between these  networks and is not willing to invest in segregating them physically (expensive), you can go ahead with VLAN.

 

If you don't have such a requirement, it's best to stay with your current setup.

We have several production setups where we use VLANs over bonding.

This works very well: On a server with 4 interfaces, we have

1 OAM NIC

1 NIC dedicated to HA purposes (corosync)

2 NICs as bond. Over this bond, we have several (usually 2-5) VLANs running.

 

This allows traffic separation (with as many VLANs as you need on the bond: just create a new bond0.X and assign an IP to it ...) and makes configuration of the firewalls around those production servers easier and more efficient.

 

We only used that with IPv4 so far, and that setup did not create any problems.

We use VLAN over bonding (mode 6). It works just fine. The only thing I don't like is I can't install Linux over network (i.e. nfs, ftp, http, etc.).

Hello Tony, based on your description I think you are searching for something like:

 

- How to use bonded interfaces in specific applications?

https://access.redhat.com/kb/docs/DOC-47348

 

- How do I set up VLAN (802.1q) tagging on a network interface in RHEL 5?

https://access.redhat.com/kb/docs/DOC-47489

 

Cheers!

We used VLANs in connection with bonding in RH5 and it worked like a charm!

However, when we moved to RHEL6 we ran into issues.

 

The doc that Priscila mentioned is sufficient to set it up, but in every case I would recommend to

- use latest initscripts you can get

- check your kernel errata as there are really issues when it comes to the combination of VLAN and bonding at least

 

I think bonding in connection with VLAN is the main usecase because you anyway need a switch configured on the other end of the cable and probably want redundant cabling...During our first attempts to use this setup we faced issues like no redundancy in the bond, lost static routes after reboot, kernel panics after few cluster failovers and all crap. But: With some RHpacthes/updates, fiddling and contacting RedHat support, we got it working. Use ethtool and closely monitor /proc/net/bonding in case you want to bond your VLANs. After all, I think it is absolutely worth trying !! We are "happy" now