Hi all,

Since the later part of last year, I've experienced problems with DHCP
leases on Windows PC's. It's not related to the DHCP server as I use a Routerboard to host my DHCP server while my friends more commonly use
their ISP supplied router. I've taught a number of people how to open a Command Prompt and do an "ipconfig /release" followed by a /renew and it consistently resolves the problem but it soon reoccurs.

The problems seems confined to Windows PCs running v8 or v10 which makes
me suspect a recent update. Is anyone else experiencing the same thing?

Thanks,
Steve
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Thu, 26 Jan 2017 15:30:21 -0000 (UTC), Steve Crook <steve@mixmin.net>
wrote:

Since the later part of last year, I've experienced problems with DHCP
leases on Windows PC's.

What are the specific problems? Some examples:
- Lease shorter than expected?
- Lease longer than expected?
- Lease being allowed to expire, not renewed as expected?
- Lease assigns an unexpected IP address?
- Other?

It's not related to the DHCP server as I use a
Routerboard to host my DHCP server while my friends more commonly use
their ISP supplied router.

How does that indicate that it's not a problem with the DHCP server?

I've taught a number of people how to open a
Command Prompt and do an "ipconfig /release" followed by a /renew and it >consistently resolves the problem but it soon reoccurs.

Does "a number of people" indicate that there are others around you who
are experiencing the same DHCP issue(s)? What do you all have in common?

What does "it soon reoccurs" mean? Does soon refer to seconds, days, or something in between?

The problems seems confined to Windows PCs running v8 or v10 which makes
me suspect a recent update. Is anyone else experiencing the same thing?

I'm not seeing it here on 7, 8.1, or 10.
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Thu, 26 Jan 2017 12:19:07 -0600, Char Jackson wrote in
Message-Id: <tvek8ctbs8fomev9945lmp9u92l2isluh1@4ax.com>:

On Thu, 26 Jan 2017 15:30:21 -0000 (UTC), Steve Crook <steve@mixmin.net> wrote:

Since the later part of last year, I've experienced problems with DHCP >>leases on Windows PC's.

What are the specific problems? Some examples:
- Lease shorter than expected?
- Lease longer than expected?
- Lease being allowed to expire, not renewed as expected?
- Lease assigns an unexpected IP address?
- Other?

Client appears to lose its lease at expiry but doesn't attempt to renew.

It's not related to the DHCP server as I use a
Routerboard to host my DHCP server while my friends more commonly use
their ISP supplied router.

How does that indicate that it's not a problem with the DHCP server?

It indicates the problem isn't specific to a single DHCP service. A
further indication is that the problem is only impacting Windows
clients. Devices running Android, Linux, Raspbian, etc don't appear to
be impacted.

I've taught a number of people how to open a
Command Prompt and do an "ipconfig /release" followed by a /renew and it >>consistently resolves the problem but it soon reoccurs.

Does "a number of people" indicate that there are others around you who
are experiencing the same DHCP issue(s)? What do you all have in common?

Yes, I work in the IT industry and frequently help out friends and
relatives with issues. My initial thought was a problem with the BT
hub (common in the UK) but my partner's Windows 10 laptop is now
frequently experiencing the same issue. Notably, my Windows 10 PC with
a static lease appears to be unaffected.

What does "it soon reoccurs" mean? Does soon refer to seconds, days, or something in between?

My DHCP server lease is 3 days. This is consistent with when the
problem manifests.

The problems seems confined to Windows PCs running v8 or v10 which makes
me suspect a recent update. Is anyone else experiencing the same thing?

I'm not seeing it here on 7, 8.1, or 10.

Thanks, I wanted to see if it was a broadly experienced issue before
trying to isolate it with settings changes.
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Thu, 26 Jan 2017 19:16:34 -0000 (UTC), Steve Crook <steve@mixmin.net>
wrote:

On Thu, 26 Jan 2017 12:19:07 -0600, Char Jackson wrote in
Message-Id: <tvek8ctbs8fomev9945lmp9u92l2isluh1@4ax.com>:

On Thu, 26 Jan 2017 15:30:21 -0000 (UTC), Steve Crook <steve@mixmin.net>
wrote:

Since the later part of last year, I've experienced problems with DHCP >>>leases on Windows PC's.

What are the specific problems? Some examples:
- Lease shorter than expected?
- Lease longer than expected?
- Lease being allowed to expire, not renewed as expected?
- Lease assigns an unexpected IP address?
- Other?

Client appears to lose its lease at expiry but doesn't attempt to renew.

Use ipconfig /all to see the DHCP lease info. Here's mine:

Ethernet adapter Ethernet:

DHCP Enabled. . . . . . . . . . : Yes
Lease Obtained. . . . . . . . . : Thursday, January 26, 2017 4:09:59 PM
Lease Expires . . . . . . . . . : Friday, January 27, 2017 6:10:00 PM
DHCP Server . . . . . . . . . . : 192.168.0.1

Has the lease actually expired? When you manually renew it, do you get a
new IP, and is your old IP already assigned to another client?

Do you lose network connectivity (LAN) when you see this issue?

https://technet.microsoft.com/en-us/library/cc958935.aspx
the client is responsible for renewing the lease. By default, DHCP
clients try to renew their lease when 50 percent of the lease time has
expired. To renew its lease, a DHCP client sends a DHCPRequest message
to the DHCP server from which it originally obtained the lease.
The DHCP server automatically renews the lease by responding with a
DHCPAck message.

With a lease time of 3 days, clients should start trying to renew when
1.5 days remains on the lease, so if you use ipconfig and you see a
lease that's far past that point, something went wrong with the lease
renewal.
--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)