SCCM PXE not getting IP address - sccm

Our organization uses SCCM 2016 connected to two MS Server 2016-based DPs. The first works fine though the other recently (last 30 days or so) stopped communicating with the PXE. We don't know what exactly caused this (perhaps a CU update?). Essentially, when pressing F12 to start PXE, we don't get any IP address.
The process goes as follows:
>>Checking Media Presence......
>>Media Present.......
>>Start PXE Over IPv4 (MAC address)
In attempt to get it to work, I have restarted the DHCP server and set up a new DP, the problem persists.
Our servers are up-to-date with the latest Microsoft update (which at this point we would not like to revert due to security reasons). What would you guys suggest me do?
Thanks in advance!

Make sure you have configured DHCP Options 66 and 67 on the scope where you attempt to boot to PXE.
Since it looks like you attempt to boot from UEFI, it will be better for you to setup a DHCP Policy to direct UEFI and BIOS clients to the correct file each time. Here's a great tutorial for setting this up

Related

Can't reach Azure App Service from within my private LAN on a windows machine

This morning I noticed that none of the web apps I am running in Azure is reachable anymore.
I first thought its an issue with Azure itself, but when I try to connect with a mobile hotspot (through my phone) everything works as expected.
The problem seems only to exist in my own LAN at home but only Azure is affected.
When I try to navigate to a website, I get the following message:
I also cannot nslookup it:
I do not have any problem with surfing the internet. All other sites work fine... but I don't even know where to start on solving this problem.
Does anybody know a tool to diagnose this? What could be wrong here...?
I did not have any issues with accessing the services yesterday.
In recent years, DNS has become the most vulnerable part of the internet, as many other components are strengthened significantly.
Like you discovered, for some unknown reasons the DNS your machine connects to failed to sync the proper Azure related records. That's not an uncommon issue if you read about how badly DNS infrastructure around the globe was maintained.
Usual solutions are,
Switch to other DNS service than your default ISP provided ones, Google/Cloudflare public DNS servers are popular, and there are many other good options.
Hack your hosts file (but that's too complicated).
Since you had no Problems yesterday, my first question is: Did you change anything in your local Network?
Maybe some new Firewall rules or maybe some entry in your Host File for testing?
When you try to access Azure with only the IP, does that work? If yes then you have to look at your DNS.(maybe try Google DNS 8.8.8.8)

How to wait for network connectivity before starting a service in Windows?

I'm attempting to use Suricata IDS for monitoring the network events in a specific interface.
I have been able to install the service and I am able to execute it.
Everything seems to be working fine, except for the fact that the service might fail to start at computer startup.
The service in fact necessarily needs to have the connection ready and available (assigned IP, etc.) when Windows starts it.
So, the service is working correctly at startup ONLY when the network is up and running for that interface.
If for some reason the network connection comes up later than usual, the service fails to start, and Windows seems to not try again to start it.
I've been looking at other stackoverflow questions in order to correctly set the dependencies for the network connection and for what I'm trying to do, but they seem to not be working.
So, what are the correct dependencies to add to my service for instructing Windows to wait for the network connection to be up and running (IP already assigned, DNS already set, etc.) before starting it?
If you have an alternative idea on how to solve the problem you're welcome to post a reply.
Any suggestion is appreciated.

NETGEAR Router: DNS Server Not Responding

I'm running Windows 7 64-bit Professional edition and I've been using NETGEAR Router WNR612v3 for a while now. I'm not a professional in networking, but apparently the DNS server all of my computers in this house use is not responding. All the computers network card settings are set to automatic, both in resolving an IP address and resolving a DNS server.
I've had this issue all morning and fixed it by making my main computers DNS server static listening to one of GOOGLEs public DNS server (208.67.222.222) and that works perfectly. I then put my computer back to automatically resolve a DNS server and went to NETGEARs control panel by accessing my default gateway address (192.168.x.x) and configured the DNS address settings. I set it to automatically get one from my ISP (Bahnhof SE). That didn't work, so I've set it to static and tested three addresses at a time using all of these:
213.80.98.2
213.80.101.3
208.67.222.222
8.8.8.8
8.8.4.4
with no avail. It seems that my computers just won't resolve the DNS server given by NETGEAR, or I'm just understanding this wrong. But the end result is that my computer is obviously not receiving the Public GOOGLE DNS server that I've set on the NETGEAR DNS Addresses configuration. Here are a few screen shots:
Screenshot #1
Screenshot #2
Screenshot #3
Screenshot #4
Any suggestions are greatly appreciated! Thank you in advance.
with the limited information you provided all I can do is speculate that the firmware on your router is outdated or faulty, try updating the firmware or connect to an open Wi-fi network to ensure that the router is the problem. You will have to find where the problem is to fix it. My bet is on the router based on the fact that several computers within your house are having the same issue, and when adding the dns server address statically on the computers it works. So update the firmware, if that doesn't work go buy another router.

3 layer application non networked?

I have a system named Windchill which runs in a CentOS 5.7 virtualbox;
The system consists of apache, oracle 11g, listener, windchillDS(openLDAP) and the application core (method server) which is a java process. All installed in the same vm(monolithic)
My question is related with the network, The system runs smooth on the network, but once I remove the network cable it stops working and the method server keeps restarting with the socket timeout error.
Im not a IT specialist, I manage the internal configuration of the system and I dont have an specialist to help me right now but I need desperately to make it run non networked in a laptop to show it for a customer.
I just want a hint of where may be the problem:
Does oracle runs non networked? Which configurations do I need to make it run without a network?
Maybe the problem is the listener?
I guess the problem is the oracle because of the socket timeout error with the database but Im not sure...
Sorry this is long and probably needs more explanation, please ask whathever you want!
I found this tip in another forum specific for the windchill product(login needed)
http://portal.ptcuser.org/p/fo/st/thread=52005&posted=1
It is related with Linux configuration to resolve the IPs:
"Edit your /etc/resolv.conf to look like this when not connected to a network:
domain local domain
search localdomain
nameserver 127.0.0.1"
Worked perfectly!
Thank you for your prompt answers guys!!!

My IP seems to be blocked by web hosting server

I have a strange problem, I just installed my php web site on a shared hosting, all services were working fine. But after configuring my app I just could visit my web site only once, other attempts gives:
"The server is taking too long to respond.".
But from other IP i can access, but only once, it seems all ip addressess beeing blocked after first visit(even ftp and other services get down, no access at all from the IP), can anyone help to explore this problem ? I don't think that it's my app problem, the app works fine on my local PC.
Thanks.
First thing to try would be a traceroute to determine where your traffic is being blocked.
In a windows command prompt:
tracert www.yoursharedhostingserver.com
At the moment, trying to access this address gives this:
Fatal error: Class 'mainController'
not found in
/home/myicms/public_html/core/application/crApplication.class.php
on line 181
I have tried it multiple times and it didn't block me. It might be that You have already solved this problem.
As far as I know, the behavior described by You could only be explained by a badly configured intelligent firewall. It may have been misconfigured by Your host.
If You visit a site at a certain host and suddenly You cannot access an ftp on this host, then it's either a (really bad) firewall or a (very mean) site that explicitly adds a firewall rule to ignore that address.
Some things that You might look into:
It might be something with identd too. What was the service You have configured on Your host? Was it by any chance any kind of server-controll panel (that might have an ability to controll a firewall)?
Is the blockade permanent, or does it go off after 24h, or does it only go off after rebooting the server? Does restarting some services makes the blockade go off?
Did You install any software that "protects Your server from portscanning"? It might be a bit too aggressive.
I wish You good luck in finding a source of this problem!
Chances are that if you can access it once that its actually working. The problem is more than likely in the php code than in the server.

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