DHCP Address seemingly not releasing

G

Guest

I am having a couple of problems with our DHCP services on our Windows 2000
Servers. Our DHCP arrangement is unusual in that each user occupies a vlan
(one user per vlan), with only one user and one IP address per scope. The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the client may
or does initiate lease renewal at intervals less than the lease time. I have
also heard that once the lease time is reached and the client no longer
responds to the server, the server keeps the client information (24 hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does not
appear in the leased address window), but does not allow the address to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and selecting
"Display Stastistics" we discovered that Total Address = 1 (expected) and
Address in Use = 1 (unexpected). The address has been released and lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac
 
P

Phillip Windell

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).
 
G

Guest

Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


Phillip Windell said:
I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).
 
G

Guest

For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


Phillip Windell said:
I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


RMac said:
Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows 2000
Servers. Our DHCP arrangement is unusual in that each user occupies a vlan
(one user per vlan), with only one user and one IP address per scope. The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the client may
or does initiate lease renewal at intervals less than the lease time. I have
also heard that once the lease time is reached and the client no longer
responds to the server, the server keeps the client information (24 hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does not
appear in the leased address window), but does not allow the address to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and selecting
"Display Stastistics" we discovered that Total Address = 1 (expected) and
Address in Use = 1 (unexpected). The address has been released and lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


Rich Holmes said:
For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


Phillip Windell said:
I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

If you want to sniff it out and send a capture file, I'll tell what I see.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


Rich Holmes said:
For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

I personally think there's another device grabbing the IP. Not sure how it's
set up at layer 2. I used to have a connection like that when I worked at an
ISP and set up DSL. I used to have PPPoE used to pull an address. You need
to make sure that no other machines are on that broadcast domain.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


Rich Holmes said:
For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Rich,

I'm not too far from your opinion in that regard. However, I am not aware
of any tool that I can use to verify something of this nature. As a
precautionary meature I've started the "dog" work of checking all the masks.

This is a small company (two bobs and a truck and I do mean tow bobs) I've
stressed my concerns to managment several times about a "sniffing" device. I
think we might have one on the scene in the the next month. That should tell
me who is getting the address as you alluded in your post.

Wish me luck.

Cheers,

Mac

--
We are not Borg...


Rich Holmes said:
I personally think there's another device grabbing the IP. Not sure how it's
set up at layer 2. I used to have a connection like that when I worked at an
ISP and set up DSL. I used to have PPPoE used to pull an address. You need
to make sure that no other machines are on that broadcast domain.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


Rich Holmes said:
For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Where you able to test it using my suggestionns? If so how did it go?
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

I'm not too far from your opinion in that regard. However, I am not aware
of any tool that I can use to verify something of this nature. As a
precautionary meature I've started the "dog" work of checking all the masks.

This is a small company (two bobs and a truck and I do mean tow bobs) I've
stressed my concerns to managment several times about a "sniffing" device. I
think we might have one on the scene in the the next month. That should tell
me who is getting the address as you alluded in your post.

Wish me luck.

Cheers,

Mac

--
We are not Borg...


Rich Holmes said:
I personally think there's another device grabbing the IP. Not sure how it's
set up at layer 2. I used to have a connection like that when I worked at an
ISP and set up DSL. I used to have PPPoE used to pull an address. You need
to make sure that no other machines are on that broadcast domain.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


:

For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Rich,

Not yet. I won't be able to check this out until it happens again. The
call center does not have the specific information (a new employee) I need to
chase this. Regardless, the managers want answers and as I soon as we get
some I'll be sure to drop a line here....

Cheers,

Mac

--
We are not Borg...


Rich Holmes said:
Where you able to test it using my suggestionns? If so how did it go?
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

I'm not too far from your opinion in that regard. However, I am not aware
of any tool that I can use to verify something of this nature. As a
precautionary meature I've started the "dog" work of checking all the masks.

This is a small company (two bobs and a truck and I do mean tow bobs) I've
stressed my concerns to managment several times about a "sniffing" device. I
think we might have one on the scene in the the next month. That should tell
me who is getting the address as you alluded in your post.

Wish me luck.

Cheers,

Mac

--
We are not Borg...


Rich Holmes said:
I personally think there's another device grabbing the IP. Not sure how it's
set up at layer 2. I used to have a connection like that when I worked at an
ISP and set up DSL. I used to have PPPoE used to pull an address. You need
to make sure that no other machines are on that broadcast domain.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


:

For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 
G

Guest

Thanks, good luck.
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

Not yet. I won't be able to check this out until it happens again. The
call center does not have the specific information (a new employee) I need to
chase this. Regardless, the managers want answers and as I soon as we get
some I'll be sure to drop a line here....

Cheers,

Mac

--
We are not Borg...


Rich Holmes said:
Where you able to test it using my suggestionns? If so how did it go?
--
Network Engineer
MCSE, MCSA, A+, Network+


RMac said:
Rich,

I'm not too far from your opinion in that regard. However, I am not aware
of any tool that I can use to verify something of this nature. As a
precautionary meature I've started the "dog" work of checking all the masks.

This is a small company (two bobs and a truck and I do mean tow bobs) I've
stressed my concerns to managment several times about a "sniffing" device. I
think we might have one on the scene in the the next month. That should tell
me who is getting the address as you alluded in your post.

Wish me luck.

Cheers,

Mac

--
We are not Borg...


:

I personally think there's another device grabbing the IP. Not sure how it's
set up at layer 2. I used to have a connection like that when I worked at an
ISP and set up DSL. I used to have PPPoE used to pull an address. You need
to make sure that no other machines are on that broadcast domain.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Rich,

Thanks for idea. I'll give that a shot with the next customer. Any
thoughts why the address would not become available after release? The lease
time is set for 30 miinutes....

Cheers,

Mac
--
We are not Borg...


:

For testing, make an exclusion excluding the one valid IP address. Then make
a reservation in that scope using the client's MAC address. This way the
only device that could ever get that IP address is that client. I sometimes
use this method when I want to enable PXE imaging which requires DHCP in a
static environment. It will stop the DHCP server from giving out any IPs
that it doesn't have a specific reservation for. Let me know if that helps.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

Phillip,

Thank you for your conern. This is an odd environment. My company is a
"mimi me" ISP and as such is somewhat a kludge of networking hierarchies. We
are using the servers for DHCP.
--
We are not Borg...


:

I know this isn't what you post is about,...but...

If you have Active Directory then you need to stop using the ISP's DNS in
the Scopes and start using only your AD/DNS and nothing else. The ISP's DNS
will go in the Forwarders List within the config of your AD/DNS Server (and
nowhere else).

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


Rich,

A typical scope looks like this:

IP Network:192.168.104.204
Mask: 255.255.255.252
DFGW:192.168.104.205
Address (Starting): 192.168.104.206 (The only leased IP address in the
range.)
Address (Ending): 192.168.104.206
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

One scope exists for each customer. Considering the previous example the
next scope looks like this:

Address: 192.168.104.208
Mask 255.255.255.252
DFGW 192.168.104.209
Address (Starting): 192.168.104.210
Address (Ending): 192.168.104.210
DNS 1: (ISP's DNS)
DNS 2: (ISP's DNS)

Does this help?

Cheers,

Mac



--
We are not Borg...


:

provide more information such was scope network address and subnet mask.
--
Network Engineer
MCSE, MCSA, A+, Network+


:

I am having a couple of problems with our DHCP services on our Windows
2000
Servers. Our DHCP arrangement is unusual in that each user occupies a
vlan
(one user per vlan), with only one user and one IP address per scope.
The
lease period is 30 minutes.

The first problem occurs almost weekly we are having to "release" IP
addresses for our users before they can lease an address. I have read
several artical and learned through other tech resources that the
client may
or does initiate lease renewal at intervals less than the lease time.
I have
also heard that once the lease time is reached and the client no
longer
responds to the server, the server keeps the client information (24
hrs?)
incase the client request the address at a later date.

The second problem is similar in that the address is released (does
not
appear in the leased address window), but does not allow the address
to lease
w/o rebuilding the scope. While troubeshooting this problem, we've an
anolomly (we think). Highlighting the scope, right clicking, and
selecting
"Display Stastistics" we discovered that Total Address = 1 (expected)
and
Address in Use = 1 (unexpected). The address has been released and
lease has
expired.

Your thoughts greatly appreciated.

Cheers,

Mac
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top