Home
Join

23 Replies

  • What NIC is it using?  What drivers are you using, Windows or the vendors?

    Was this post helpful? thumb_up thumb_down
  • Any MAC filtering within the DHCP server?

    Spice (1) flagReport
    Was this post helpful? thumb_up thumb_down
  • The client is using a Broadcom NetLink Gigabit Ethernet NIC; the server is using a Broadcom NetXtreme Gigabit Ethernet on NIC1 (NIC2 is disabled).  The driver provider on the client is Microsoft.  On the server is one provided by Broadcom.

    Where would I check MAC filtering?  I don't remember programming that in.

    Was this post helpful? thumb_up thumb_down
  • I’d verify that the MAC of the problem child isn’t in the DHCP server’s deny list.

    Spice (2) flagReport
    Was this post helpful? thumb_up thumb_down
  • Here's the Filters tab:

    There's nothing in the tree either.

    Was this post helpful? thumb_up thumb_down
  • RedAlertConsulting wrote:

    The client is using a Broadcom NetLink Gigabit Ethernet NIC; the server is using a Broadcom NetXtreme Gigabit Ethernet on NIC1 (NIC2 is disabled).  The driver provider on the client is Microsoft.  On the server is one provided by Broadcom.

    Where would I check MAC filtering?  I don't remember programming that in.

    What brand/model is the client?

    Was this post helpful? thumb_up thumb_down
  • The client is a Dell Vostro 230.  The NIC is a Broadcom NetLink (TM) Gigabit Ethernet.

    Was this post helpful? thumb_up thumb_down
  • I'd try to change the client's MAC address temporary to be sure that there is no problem with it. Additionally will try with an external USB LAN card.

    Was this post helpful? thumb_up thumb_down
  • Check if the DHCP Client service is enabled and running.
    If it is, install wireshark on client and capture the DHCP packets.If that doesn't show you any incoming DHCP Offer packets, also install it on the DHCP server.
    Save and combine the 2 captures to follow the entire conversation.

    Spice (1) flagReport
    1 found this helpful thumb_up thumb_down
  • Check your DHCP address pool. It should have enough addresses to handing out to the clients. Try restarting the DHCP service likewise.

    Was this post helpful? thumb_up thumb_down
  • I'd second installing wireshark and seeing what packets are being sent and received.

    Also, I'd be checking (or changing) the switch port that the client is connected to - is there a possibility that it's on a different VLAN and there's no IP helper in place?

    Spice (1) flagReport
    1 found this helpful thumb_up thumb_down
  • Nah, it's an unmanaged switch.

    I'll try installing Wireshark but not sure when I'll have a chance to go back to the office.

    0 of 1 found this helpful thumb_up thumb_down
  • There should also be a DHCP event log in Windows

    Spice (1) flagReport
    Was this post helpful? thumb_up thumb_down
  • Check the client event logs, if it's failing to get an IP it should list why there.

    Spice (2) flagReport
    Was this post helpful? thumb_up thumb_down
  • Here's something unusual to check.

    It's unlikely to be the case, and the supply chain was theoretically designed to make it as close to impossible as is practical, but have you checked for MAC address collisions on the network?

    I've been in the industry over 20 years, and in the whole of my career, I've only encountered this issue 7 times, but it is interesting to note (if a little concerning) that 4 of those occasions were in the last 9 months. I'm starting to wonder if some manufacturers are running out of their allocation and are starting to re-use addresses, as each case involved a brand new device colliding with one that was quite old (8ish years). Multiple OEMs were involved in my cases, although as network components tend to be sourced from one of a small number of vendors, this isn't as surprising as the fact that such collisions happened at all.

    Spice (1) flagReport
    Was this post helpful? thumb_up thumb_down
  • RedAlertConsulting wrote:

    The client is a Dell Vostro 230.  The NIC is a Broadcom NetLink (TM) Gigabit Ethernet.

    What is the Speed & Duplex set to on the client? 

    Have you tried changing the values?

    Was this post helpful? thumb_up thumb_down
  • Ace:

    No i haven't tried that. They're set to whatever Windows defaults it at. What should I look for?

    0 of 1 found this helpful thumb_up thumb_down
  • RedAlertConsulting wrote:

    Ace:

    No i haven't tried that. They're set to whatever Windows defaults it at. What should I look for?

    By default those are set to Auto Negotiate, Try 1Gbps/Full Duplex.  If that doesn't work as a test, you can even try 100Mbps/Full Duplex

    Was this post helpful? thumb_up thumb_down
  • Check the DHCP logs on the DHCP server, you should not need to install Wireshark as long as you have the default DHCP logs enabled.  You should be looking for a Discover packet from the client, search the log for the MAC address the Dell client has?  If you do not see anything in the log it could be the Discover packet is not reaching the DHCP server?  You can alternatively as a test, create a static DHCP entry to see if that works.  Are there other clients on the same switch that can get an IP from the DHCP server?

    Spice (1) flagReport
    Was this post helpful? thumb_up thumb_down
  • By the way, I checked the DHCP pool and here are the recorded MAC addresses.  The desktop in question has a MAC id of F0-4D-A2-F2-31-4B.  I don't think there's a conflict here but it was a worth a look:


    Was this post helpful? thumb_up thumb_down
  • RedAlertConsulting wrote:

    The DHCP settings allow for 50 addresses and there are plenty to go around.

    • How many of these 50 are usually in use?
    • How many of these have been used in the past and are not yet ready for reassignment?
    • How many are reserved?
    • And how many are available for reassignment, on average, on minimum and on maximum?
    • Which lease times do you use when assigning dynamic IP addresses?

    RedAlertConsulting wrote:

    Is there some setting I need to change?

    I don't know if there are options to speed up clean up formerly used dynamic IP addresses. One option you have is shorten the lease time. This should also speed up the clean up of formerly used IP leases. If your current lease time uses Windows defaults of a week, you could shorten this to a calendar day (24 hours) or a working day (8-10 hours). And as long as you don't force renewal, such changed policy will spread only upon normal renewal request which would be about half a week in case of default settings.

    And as two Spiceheads have already remarked, I would expect some records in event logs for reasons why IP assignment failed and why APIPA was selected instead.

    RedAlertConsulting wrote:

    The client is using a Broadcom NetLink Gigabit Ethernet NIC; the server is using a Broadcom NetXtreme Gigabit Ethernet on NIC1 (NIC2 is disabled).  The driver provider on the client is Microsoft. 

    Please try replacing that Microsoft driver by a Broadcom driver. I recently read on our forum that Microsofts drivers for Broadcom NICs would be buggy and usually result in slow throughput (less than 2% of available throughput).

    Was this post helpful? thumb_up thumb_down
  • There have been - at most - 30 different clients over the years on our network as we have a small operation.  An address pool of 50 should suffice.  

    I can download and install the drivers but I'm not sure if I want to be stuck having to troubleshoot this over the phone if I lose internet connectivity.  I'll see if the office workers want to volunteer some time but this workstation isn't absolutely critical; it's more for the boss to be able to sit and read Israeli news.

    I'll keep everyone posted on what transpires.

    Was this post helpful? thumb_up thumb_down
  • RedAlertConsulting wrote:

    There have been - at most - 30 different clients over the years on our network as we have a small operation.  An address pool of 50 should suffice.  

    If all devices are wired, it should.

    But if they use iPhones/iPads or any type of tablet devices, especially with random mac or private address (IOS), then these can take IPs and hold them for up to your lease time before the system will offer them out again.

    Was this post helpful? thumb_up thumb_down

Read these next...

  • Spark! Pro series – 23rd May 2022

    Spark! Pro series – 23rd May 2022

    Spiceworks Originals

    Happy Monday!  Welcome to the Monday Spark!  Grab a cup of Coffee and read on! To start things off… A Monday Quotes Top 10. 1. Monday should be optional. 2. Good morning. Keep calm and pretend it’s not Monda...

  • Need help preparing company computers for sale (intune)

    Need help preparing company computers for sale (intune)

    Windows

    Hi Folks,              The Company I work for has just sold off its sales operation. As part of the sale, several laptop & desktop computers that were used in the sales department will be taken to the new companyMy Director has asked me to effectively pre...

  • IP Camera Monitoring System REQUIREMENT

    IP Camera Monitoring System REQUIREMENT

    Hardware

    Hello,I have:1- 150 HIKVISION IP camera 4MP 2- 5*32-CH HIKVISION NVR I want to display a live view of the 150 camera on a video wall.What is the additional required devices should I have?I think I just need a video wall controller and a high performance p...

  • What do you geek out about?

    What do you geek out about?

    Spiceworks

    In honor of Geek Pride day on May 25th, we want to know about your unique hobbies and interests and all the things you could spend hours talking about.Are you a huge comic book fan?  Do you love creating megastructures out of LEGO bricks?  Are you int...

  • Snap, AD auth fixes, Canada bans Huawei, Linux, space lasers, & Daredevil

    Snap, AD auth fixes, Canada bans Huawei, Linux, space lasers, & Daredevil

    Spiceworks Originals

    Your daily dose of tech news, in brief. Welcome to not only Friday, but according to Lonny6654 who wrote today's community-created Spark article, it is also World Bee Day. To raise awareness of the importance of pollinators, the threats they face, ...