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2019-07-31 17:48:11 +0000 asked a question Windows updates issue

Windows updates issue We noticed recently (when our print server crashed trying update via WSUS) that certain subnets ar

2019-07-25 11:59:03 +0000 marked best answer bad ip address - possible DHCP/DNS?

I will preface by saying I am new to Wireshark, so what I'm seeing is a bit overwhelming which is why I'm here :) I've picked up on a few tips regarding filtering to narrow down the data as much as possible, but to be honest I'm still not quite sure what I am looking at regarding this issue and I apologize as I'm sure it's obvious.

The issue: since I've started here about two years ago, randomly (it seems, may happen twice a day or once a month) a client will not be able to connect to the Internet or any network resources, although ipconfig shows an address within the proper scope, as well as correct mask/gateway and DNS servers. I've been reserving the affected IP address in DHCP with a bogus MAC address and then release/renew on the affected computer so the computer will pick up a new address, at which point it's on its merry way. I've then tested with deleting the reservation and had another computer pick up the address and no issues, so the issue never seems to be consistent with a given IP address. Also I've noticed the MAC address is registering when I check the machine on the DHCP/DNS server and that is as much as I've confirmed. I've come across a few posts via Google but no pertinent solutions.

I'll link to the pcap file if anyone is available for assistance, I will be happy to answer any questions or obtain more information. Also if I eventually figure it out I'll be sure to post an update.

https://www.cloudshark.org/captures/37721f76e2bf

Client address: 10.29.0.38

DNS & DHCP servers: 192.168.10.28 / 192.168.11.28

2019-07-25 11:59:03 +0000 received badge  Scholar (source)
2019-07-18 13:59:22 +0000 commented answer bad ip address - possible DHCP/DNS?

Rooting around in the DHCP server I noticed lease time for this scope was set to 2 hours..... changed it to 3 days to se

2019-07-18 12:59:14 +0000 commented answer bad ip address - possible DHCP/DNS?

Wow, I got so caught up on that not being the issue since I wasn't seeing a duplicate IP in the DHCP scope and I hadn't

2019-07-17 19:12:40 +0000 commented question bad ip address - possible DHCP/DNS?

That's just my interpretation of the issue given my lack of knowledge at this point. Since a given client is effectively

2019-07-17 17:58:06 +0000 commented question bad ip address - possible DHCP/DNS?

My apologies. Windows clients, mix of 7 and 10 and has happened on both. When this issue occurs, they are not able to ac

2019-07-17 17:45:32 +0000 commented question bad ip address - possible DHCP/DNS?

In case this helps narrow it down further, I did a release/renew (either on this pcap or while monitoring another one) a

2019-07-17 17:43:57 +0000 commented question bad ip address - possible DHCP/DNS?

In case this helps narrow it down further, I did a release/renew (either on this pcap or while monitoring another one) a

2019-07-17 17:30:55 +0000 asked a question bad ip address - possible DHCP/DNS?

bad ip address - possible DHCP/DNS? I will preface by saying I am new to Wireshark, so what I'm seeing is a bit overwhel