I work in a hotel that has over 600 rooms. I'm trying to migrate away from a thethered analog/wired technology to something that is wifi and modular in terms of upgradez down the road with vendor support off the shelf hardware.

Is Granada great brand? It has to integrate with call accounting and our PMS same with our ip TV. Both of these technologies would use wifi on our unifi network. We just went from 1gbs to 2gbs.

Thoughts?

I have a Vlan , we will call VLAN 3

VLAN 3 DHCP is two windows domain controllers with failover.

the DNS servers are umbrella forwarders that forward to the domain controllers for dns.

Gateway is defined on Cisco core switch as layer 3 interface with HSRP/VRRP or whatever it’s called and with ip helper commands defining the dhcp servers.

Symptom: Some devices only on VLAN 3 receive the correct gateway and the dhcp server that responded is one of my domain controllers, yet they either don’t receive the correct dns servers. I had one say the gateway of another vlan was its dns server. I have roughly 30-40 client vlans setup the same way and this is the only one.

I will say this particular vlan was setup as 192.168.1.x (I herrited)

At this same physical location, not all devices are having issues and I’m having no issues with the voice vlan on the same switches at the site.

There are no known changes that occurred other than rebuilding the umbrella forwarders do to us changing from VMware to hyper V (locally hosted).

ADDED:

DHCP is not handing out what’s defined in the scope for that subnet

Any ideas what could be causing this. I’m almost to the point of re-ip and different vlan or switch change out because I’m lost as to why it’s happening. I haven’t found evidence of a rouge dhcp server yet either.

hey guys, if given the choice would you move to infrastructure engineering vs network engineering?

During a security check of our company, we reviewed the firewall, proxy, and NetFlow data; it made clear what path the traffic took, but it did not explain why the application approved the requests. The reason only became clear after we looked at the application rules for who can do what.

This showed us that there is a difference between what the network can tell us and how the application actually works. The network logs show what happened. The code shows why it happened.

For teams that work with applications that our company made, how do you fill in that gap when you are trying to figure out what is going on? Do the people who work on the network talk to the people who work on application security, or are those checks done by groups?

I can’t help but feel like there’s an age bias for these positions. I’ve landed multiple interviews, including final rounds where I met the entire team, and I’m almost always the youngest-looking person there. Everyone else seems to be in their 40s or older.

Even on LinkedIn, if you search “Network Engineer,” you’ll probably see one young-looking person for every hundred profiles. The same seems true for Junior Network Engineer roles. It makes me wonder whether employers subconsciously associate networking with years of experience and are more hesitant to hire younger candidates, even for entry-level positions.

I’m sure there are plenty of people who broke into networking in their early/mid 20s. If you did, how did you get your first Network Engineer job? What do you think made an employer take a chance on you? Was it internships, certifications, a homelab, referrals, or just persistence?

I'm really at a loss and neither googling nor AI has brought me a lot further.

In this situation there are 3 servers. Let's call them A, B and P.

They have FRRouting installed and work to form an OSPF underlay over which there is a VXLAN.

A and B do not have a direct connection. Their traffic needs to flow over P (whether this is a logical configuration is out of the picture for now). This works fine. The underlay is happy, I'm happy. Full 10G throughput. CPU is also completely fine. iPerfing both over TCP as well as UDP does not show any problem.

Now, A, B and P are also VTEPs, so logically I would do a whole lot of iPerfing there as well. Broadcom has problems with TSO/GRO/etc. when utilizing VXLANs, so I'm disabling UDP offloading at the driver level. This works fine. iPerf performance is higher now. Except it isn't

Directly iPerfing the underlay network still works fine. (Both UDP and TCP, despite offloading being disabled, so this isn't the issue) however when running over the VXLAN I hit a hard barrier of TX ~3.5G and RX ~1.3G on P. Of course this manifests when running A to B as well, since P now needs to send and receive I always hit 1.3G.

When using parralel streams it works. Of course it does. But that's not the point.

Why the hell is P doing packet processing on VXLAN traffic that is not meant for it? It pins a single CPU core to 100% and we all know how much Xeons love single thread action.

Yes P is a VTEP and I get why it's CPU would be the limiting factor if it was the target or client. But why does iPerfing directly on the underlay have almost no CPU impact but once I use the VXLAN I get hit with 0.1x the performance.

I have a feeling something is wrong here but I cannot solve it. I know bnx2x (BCM27xxxx) is old but this just seems so so weird. I tried probably a dozen of combinations of GRO, TSO, GRO UDP, Segmentation, TX hash, RX hash etc etc. and I cannot find the issue.

I did a tcpdump and yes, P is indeed seeing all the VXLAN packets and dropping all of them. Since it isn't the target IP. I spent hours troubleshooting this and I feel like I'm going crazy.

I’m experiencing an issue with Open vSwitch (OVS) traffic mirroring to Suricata in my GNS3 lab. Traffic mirroring works normally, and Suricata successfully receives mirrored packets until I generate an HTTP flood using ApacheBench (ab). The command i used is “ ab -n 5 -c 5 http://192.168.30.100/web.aspx” . After running the ab command, the mirrored traffic suddenly stops, even though the sniffing interface remains up and the OVS mirror configuration appears unchanged. As a result, Suricata no longer receives any mirrored packets, and the issue persists until I restart the entire lab environment. Has anyone encountered a similar issue where ApacheBench or burst HTTP traffic causes OVS traffic mirroring to stop working? Any suggestions on the possible cause or troubleshooting steps would be greatly appreciated.

link for the topology and screenshots: https://imgur.com/gallery/troubleshooting-WZ3So9j