Static IP: Router or Windows

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Hello everyone, new guy here with some questions. I’ll get into some more detail in following posts but this question pertains to static IP’s. My understanding is static IP’s can be set via the router and also via Windows. What is the difference and the preferred method? Currently I have my computers and devices set with static IP’s from within my router (Asus RT-AC66R). Thanks!

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IP addresses must be unique and if you set the address manually in Windows you may make a mistake and have two the same. Your router can (should always) assign IP addresses and it will not allow two to be used at the same time. Whether you reserve the addresses or let the router manage them is up to you.

Personally I don’t use static addresses, the router does a great job on it’s own and I can talk to my printer via its DNS name no matter what the IP is.

cheers, Paul

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IP addresses must be unique and if you set the address manually in Windows you may make a mistake and have two the same. Your router can (should always) assign IP addresses and it will not allow two to be used at the same time. Whether you reserve the addresses or let the router manage them is up to you.

Personally I don’t use static addresses, the router does a great job on it’s own and I can talk to my printer via its DNS name no matter what the IP is.

cheers, Paul

Paul, thanks for the reply. As I am trying to integrate a home server into my network, I thought it best to create static IP’s for all my computers/devices. I left the IP addresses as my router had them assigned and just clicked the “lock” button next to each device which then made the IP address static. In my router I am able to assign a name to each device to identify them easily which I did as well. Does this sound like a good method?

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IP addresses must be unique and if you set the address manually in Windows you may make a mistake and have two the same. Your router can (should always) assign IP addresses and it will not allow two to be used at the same time. Whether you reserve the addresses or let the router manage them is up to you.

Personally I don’t use static addresses, the router does a great job on it’s own and I can talk to my printer via its DNS name no matter what the IP is.

cheers, Paul

I would agree, but occasionally we have experienced a problem. For example, let’say i put a Windows 7 PC in Sleep mode. Sometime later, i boot up a different computer. Later still, i wake up the PC that was in Sleep mode and Windows informs me that there’s an IP address conflict. It seems that the router reassigned the first PC’s IP address to the computer that i booted up later. Does this situation make a case for having the router assign static IP addresses?

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In a standard network only the server should have a static IP address, the PCs should be left as DHCP.
Depending on the set up, the server should assign IP addresses and the router is used just for access outside the local network, but on a home system you can probably stick with it as is. Make sure the server does not have a DHCP server running.

cheers, Paul

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In a standard network only the server should have a static IP address, the PCs should be left as DHCP.
Depending on the set up, the server should assign IP addresses and the router is used just for access outside the local network, but on a home system you can probably stick with it as is. Make sure the server does not have a DHCP server running.

cheers, Paul

In general this is true but wireless printers and Network disks often work better with Static IP addresses reserved in the router.

Jerry

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Thanks for the replies. So it sounds like I’ll be ok having static IP’s set in my router for a home network (without the server running a DHCP server).

Just to get a little more info, why would someone want to assign a static IP in Windows vs. the router? Does it accomplish the same thing just software vs. hardware?

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wireless printers and Network disks often work better with Static IP

I can’t see why that would be the case unless you are talking to the devices via the IP address. If you use the DNS name there should be no issues.

cheers, Paul

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I can’t see why that would be the case unless you are talking to the devices via the IP address. If you use the DNS name there should be no issues.

cheers, Paul

I have found that in a large corporate network, it is easier to map to printers if they have static IP addresses. And although I don’t often assign static IP addresses for printers in a home network, it is handy to know what the IP address of the printer is when you are mapping to it.

Group "L" (Linux Mint)
with Windows 10 running in a remote session on my file server

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Thanks for the replies. So it sounds like I’ll be ok having static IP’s set in my router for a home network (without the server running a DHCP server).

Just to get a little more info, why would someone want to assign a static IP in Windows vs. the router? Does it accomplish the same thing just software vs. hardware?

For small networks it can be easier to simply assign static IP addresses on each device rather than depend on a DHCP server running on a router or a computer. With DHCP, there’s the additional complication of dealing with not only the DHCP server but DHCP clients, IP address leases, MAC addresses and so on.

For larger networks that span multiple IP address ranges it can also be desirable to assign static IP addresses on each device to make it easier to identify each computer on the network (e.g. not all networks run Microsoft Active Directory and not all computers/devices support it).

It wasn’t mentioned in any of the earlier posts so I just wanted to clarify that there’s a difference in terminology: An IP address that is manually entered onto a computer/device is a static IP address. An IP address that is mapped to a specific MAC address by a DHCP server running either on a router or a computer is technically a fixed lease. It’s a subtle, but very important difference.

Most home networks use dynamic IP addressing — a device broadcasts a message onto the local network that it’s in need of an IP address. A DHCP server sees the request and responds with an offer. The IP address that’s offered comes with an expiration date. At what point a renewal request happens varies, but in Windows it’s typically at the halfway mark. For example, if the lease time is 3 days, Windows will try to renew its IP address at about 36 hours into the current lease.

If a device doesn’t get confirmation from a DHCP server that its lease has been renewed, it will continue to use the assigned IP address until the end of the current lease, at which point a properly designed client will release its IP address back into the local IP address pool. When the lease expires the DHCP server assumes that the client is no longer using the IP address and may reassign it to a different device (This is the situation that starvinmarvin ran into when one of his Windows PCs lost its lease while it was in sleep mode. When it woke up, before it realized that its lease had expired it had caused a conflict with another computer that had a newer lease).

Although a static IP address and a fixed lease have the effect of assigning the same IP address to a particular device each day, a fixed lease essentially offers a temporary static IP address that must be renewed on a regular basis. But unlike a dynamic IP address, the DHCP server knows that the fixed lease included an IP address that is mapped to a MAC address so it won’t reassign the IP address to a device with a different one. The IP address is reserved in the IP address pool for only that device.

As a network gets larger and/or more complex, it’s easier to manage IP addresses in one place instead of individually on each device. This is where assigning fixed leases using a DHCP server on a router helps avoid potential IP address conflicts. It’s usually less work and more reliable compared to manually configuring each device with a static IP address.

On a related note, the router doesn’t necessarily have to also be the DHCP server. A computer or other device can also be used. It could be that the DHCP server in the router stinks, is buggy, doesn’t support fixed leases, etc.

Hope I wasn’t too confusing,

Chung

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Chung – Definitely not too confusing, in fact, enlightening. It’s nice to understand those subtle differences.

FWIW, I use a static IP on my NAS device (mapped from the NAS). Why? Because the documentation said so. Everywhere else I use DHCP. First ethernet networked computer is sitting in a box waiting to be set up and I expect to use DHCP and print to it by name unless I find a reason not to.

Thanks everyone for a fun topic.
ed

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Chung – Definitely not too confusing, in fact, enlightening. It’s nice to understand those subtle differences.

FWIW, I use a static IP on my NAS device (mapped from the NAS). Why? Because the documentation said so. Everywhere else I use DHCP. First ethernet networked computer is sitting in a box waiting to be set up and I expect to use DHCP and print to it by name unless I find a reason not to.

Hi ed,

Oh yes, definitely. I’ve run across more than a few network devices (and server software) that insist on static IP addresses only without DHCP. In most cases it’s because the software can’t gracefully handle the network connection going offline even for just a moment. The worst offenders I’ve seen are desktop database programs that pretend to be in the same league as real client/server database engines. Network file sharing over NFS and SMB/CIFS aren’t a problem because clients use local caching to ride out network hiccups.

Thanks everyone for a fun topic.
ed

Agreed. 🙂

It’s these kinds of thoughtful discussions that make the forums so interesting and a learning experience.

Chung

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Yes, it does the same thing. You may want to do this in a closed network – no external access.

cheers, Paul

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If you manually set up static IP addresses in each PC, make sure that either these addresses are reserved in the router and DHCP is disabled in the router.

Jerry

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Jim, I never allow users to map to printers in the corporate environment. All printers are run from a server and the names published in AD. Then the user can just double click on the printer name and no printer IP address is involved.

cheers, Paul

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Jim, I never allow users to map to printers in the corporate environment. All printers are run from a server and the names published in AD. Then the user can just double click on the printer name and no printer IP address is involved.

cheers, Paul

When I talk about mapping printers, I speak of myself or another technician mapping a printer, not the user. I would never expect a user to map a printer using an IP address.

Group "L" (Linux Mint)
with Windows 10 running in a remote session on my file server

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Again, I don’t map printers, that’s the job of the network and it keeps admin simple.

cheers, Paul

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I have 2 printers attached to my Wireless Router via Ethernet cables, any computer I install the software on picks up/recognizes the printers and assigns the IP address. Haven’t seen a need to manually change those IPs and Wired plus Wi-Fi computers print, includes the last 4 versions of Windows, Linux Mint and Mac OS X 10.

Before you wonder "Am I doing things right," ask "Am I doing the right things?"

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My computers are always set up with a static IP address. This is the only way to tweak your router to control computers as needed. An example would be; bedroom desktop needs a port opened for P2P. This is done with Port Forwarding in your router, and the bedroom desktop has to have the same IP address every time it boots. Or your 15 year old is hogging all your bandwidth with videos and music downloads (you’re stuck with DSL). Your router can limit the bandwidth your teen monster uses. But only if you know his IP address. IE; it has to be a static IP. If these are not issues, than let Windows handle the IP addresses for you. That’s the way windows comes, out of the box with default settings, and for the average user, it’s fine.

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My computers are always set up with a static IP address. This is the only way to tweak your router to control computers as needed

You can let the router assign the addresses, then change them to reserved in the router settings. They are still assigned by the router but will not change and you can port forward all you like. The reason for doing it this way is all the control is done in the router and you don’t have to leave your chair – who wants to go into the bedroom of a teenager?!

cheers, Paul

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My computers are always set up with a static IP address. This is the only way to tweak your router to control computers as needed. An example would be; bedroom desktop needs a port opened for P2P. This is done with Port Forwarding in your router, and the bedroom desktop has to have the same IP address every time it boots. Or your 15 year old is hogging all your bandwidth with videos and music downloads (you’re stuck with DSL). Your router can limit the bandwidth your teen monster uses. But only if you know his IP address. IE; it has to be a static IP. If these are not issues, than let Windows handle the IP addresses for you. That’s the way windows comes, out of the box with default settings, and for the average user, it’s fine.

Hi mb96001,

Most home routers default to assigning IP addresses that are “sticky” — each network device gets the same IP address as before when it renews its lease. The DHCP server does this by automatically keeping track of the most recent IP address used by a particular MAC address. In a way, it’s the best of both worlds because you get pseudo-static IP addresses without having to manually set them on every device and/or maintain a MAC address table. The more often a device uses the network, the more likely it is to continue getting the same IP address. For devices like servers and network printers, those can be explicitly reserved in the router for extra measure.

As far as filtering, a good router offers the option of filtering based on MAC addresses because it’s more reliable and secure than IP addresses. It requires more computer skills to spoof a MAC address than to change an IP address to get around network controls. (On a related note, not every network card supports MAC spoofing so all of those utilities found on the Internet aren’t guaranteed to work every time.)

Although generally not an issue on home networks, MAC-based filtering also makes it easier to support more devices. Over time devices will come and go so MAC-based filtering avoids the need to track which IP addresses are still in use and which can be reused.

Chung

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