Are *you* faster than Linksys?

[MyndFyre]

OK here's my problem:

My work provides a wide-area network (the WAN) that configures static IP addresses.  We get our internet piped in through a T1 that goes through a Cisco 2415 switch that distributes network access to our computers throughout my building.  Each of these computers also has a static IP address; in the room where I'm at now, computers are 192.168.10.1-19.

I disconnected the computer with 192.168.10.19 and want to set up a wireless Linksys router to bridge the WAN onto wireless.  To do so, I've set up the wireless router with all of the static IP configuration necessary -- the IP address, subnet mask (255.255.255.0), default gateway (192.168.10.254), DNS and WINS servers.

Each of the other computers (192.168.10.1-18) do this:

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C:\Documents and Settings\student10.MINNOW>ping 192.168.10.254

Pinging 192.168.10.254 with 32 bytes of data:

Reply from 192.168.10.254: bytes=32 time=2ms TTL=255
Reply from 192.168.10.254: bytes=32 time=2ms TTL=255
Reply from 192.168.10.254: bytes=32 time=2ms TTL=255
Reply from 192.168.10.254: bytes=32 time=1ms TTL=255

Ping statistics for 192.168.10.254:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 1ms, Maximum = 2ms, Average = 1ms
You'll notice that I'm pinging the default gateway address, which should be the first thing any jumps to the WAN go through.  When I try to do this with the Linksys router though, I get packets dropped (0% returned out of 5).  I've verified that the router is set up identically to the computer that it replaced.

Any ideas?

Yes, I have tried multiple cables and ports.

[MyndFyre]

Guys, this is not you being faster than Linksys tech support. 

[Newby]

Hmm... interesting....

I don't get your network layout exactly (kinda tired and everything I read I just skimmed) but I would have recommended trying different ports on the router.

And if you can get to the gateway and the router can't, what's the problem? The router doesn't need to be able to get out if you can get out just fine.

[MyndFyre]

Linksys fixed it, you guys suck. 

[Sidoh]

Hmm... interesting....

I don't get your network layout exactly (kinda tired and everything I read I just skimmed) but I would have recommended trying different ports on the router.

And if you can get to the gateway and the router can't, what's the problem? The router doesn't need to be able to get out if you can get out just fine.

Yes, I have tried multiple cables and ports.

--

First question, why does your network use static IP's in place of DHCP?  Any particular reason?  It seems its nothing but a pain in the network administration's ass to use static IP addressing.

If that router has multiple ports, try plugging a computer into it after the router has been plugged into the network.  If that doesn't work, consider trying another router.

edit what'd they do?  Firmware upgrade?

[iago]

Incidentally, it's bad practice to discuss network arrangement on a public venue.  Especially things like IP Addresses and software/hardware types.  If you changed those IPs, then that's ok

On a larger network having either static IPs or static DHCP is useful so that rules can be made based on a user's IP.  IP obviously isn't sufficient as an access control, but it is still useful.  Other uses include assigning DNS names without having to worry that the IP will change.  That's all more useful for servers, not for workstations, though.  But static IPs are still handy.  I personally dislike DHCP

[Newby]

I do DHCP with assignment of IP addresses based on MAC addresses.

i.e. AA:BB:CC:DD:EE:FF gets 192.168.1.2, BB:CC:DD:EE:FF:AA gets 192.168.1.3, etc

[iago]

That's how it worked at the Government of Manitoba.  But I see no real point in doing that at home and I just assign all my computers static IPs. 

Plus, it's easier to keep track of them

[MyndFyre]

First question, why does your network use static IP's in place of DHCP?  Any particular reason?  It seems its nothing but a pain in the network administration's ass to use static IP addressing.

It's not my network, it wasn't up to me.

If that router has multiple ports, try plugging a computer into it after the router has been plugged into the network.  If that doesn't work, consider trying another router.

It wasn't that the router didn't work, it's that it didn't talk to the network I was connecting it to.  The wireless network that it made was fine.

edit what'd they do?  Firmware upgrade?

Shh.  It was something dumb, that I'd already tried but evidently didn't try hard enough.  The point is I had to get to tier 2 of tech support to get helped.

Incidentally, it's bad practice to discuss network arrangement on a public venue.  Especially things like IP Addresses and software/hardware types.  If you changed those IPs, then that's ok

Eh, the network itself isn't publically-available anyway, so I tend to think it doesn't matter much.

[Chavo]

I troubleshoot this kind of stuff all the time where I work, sorry I didn't see this thread faster 

edit what'd they do?  Firmware upgrade?

Shh.  It was something dumb, that I'd already tried but evidently didn't try hard enough.  The point is I had to get to tier 2 of tech support to get helped.
[/quote]

That is true for almost any large company's tech support.  Most of the time they will escalate you to tier 2 right away if you simply ask.  The tier 2 guys won't be happy about it, but hey...it's better than spending 30 minutes going through the checklist that you know you already did.

[iago]

Incidentally, it's bad practice to discuss network arrangement on a public venue.  Especially things like IP Addresses and software/hardware types.  If you changed those IPs, then that's ok

Eh, the network itself isn't publically-available anyway, so I tend to think it doesn't matter much.

That's the point -- it's a security/privacy thing.  People shouldn't know about the internal structure of a network. 

[Sidoh]

I do DHCP with assignment of IP addresses based on MAC addresses.

i.e. AA:BB:CC:DD:EE:FF gets 192.168.1.2, BB:CC:DD:EE:FF:AA gets 192.168.1.3, etc

I'm fairly sure that's how DHCP works by default.

[MyndFyre]

I'm fairly sure that's how DHCP works by default.

Not necessarily.  Newby is saying he's simulating static IP addresses through DHCP by guaranteeing that a particular MAC address gets a particular IP address.  DHCP doesn't guarantee that any MAC gets an IP, just an IP in a given range.

[Sidoh]

I'm fairly sure that's how DHCP works by default.

Not necessarily.  Newby is saying he's simulating static IP addresses through DHCP by guaranteeing that a particular MAC address gets a particular IP address.  DHCP doesn't guarantee that any MAC gets an IP, just an IP in a given range.

dhcpd (and every single other DHCP server I've worked with, including ones on multiple routers)assigns IP leases according to a MAC address.  If this weren't true, releasing and renewing in IP configuration utilities would result in new IP addresses, which, in my experience, is never the case.

DHCP servers assign leases to a certain MAC address.  They will only dismiss the leases when the expiration date rolls around or if they are manually dismissed by a systems administrator.

[Newby]

dhcpd (and every single other DHCP server I've worked with, including ones on multiple routers)assigns IP leases according to a MAC address.  If this weren't true, releasing and renewing in IP configuration utilities would result in new IP addresses, which, in my experience, is never the case.

DHCP servers assign leases to a certain MAC address.  They will only dismiss the leases when the expiration date rolls around or if they are manually dismissed by a systems administrator.

Really? I've had the opposite experience on every DHCP server I've dealt with. I had to explicitly enable the way I have it.

As for the red statement, I read somewhere that when you request a new lease, you ask for the previous lease/IP you had. If it's available, you get it back. If it isn't, you get a new one. This is how my ISP does it, anyhow.

Client: "Hi, I want a new lease."
Server: "Sure thing."
Client: "I had xxx.yyy.zzz.123, before, can I get that again?"
Server: "Sure thing. Here you go." / "Sorry, that's taken. You can have xxx.yyy.zzz.124 instead."
Client: "Thanks! See ya!"

This would explain when I used to disconnect my router for extended periods of time, it would give me a new IP, and I haven't changed IPs in over 2 years since I don't leave my router dead for over a minute. :0

[Sidoh]

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dhcpcd: MAC address = 00:e0:98:7c:82:39
dhcpcd: your IP address = 10.0.0.194

Code: [Select]

      1 # dhcpd.conf
      2 #
      3 # Configuration file for ISC dhcpd (see 'man dhcpd.conf')
      4 #
      5
      6 ddns-update-style ad-hoc;
      7
      8 subnet 10.0.0.0 netmask 255.255.255.0 {
      9     range 10.0.0.30 10.0.0.200;
     10         option subnet-mask 255.255.255.0;
     11         option routers 10.0.0.2;
     12         option domain-name-servers 10.0.0.2;
     13         option domain-name "sidoh.org";
     14         option ip-forwarding on;
     15
     16     }


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C:\Documents and Settings\sidoh>ipconfig

Windows IP Configuration


Ethernet adapter Local Area Connection:

        Connection-specific DNS Suffix  . : sidoh.org
        IP Address. . . . . . . . . . . . : 10.0.0.199
        Subnet Mask . . . . . . . . . . . : 255.255.255.0
        Default Gateway . . . . . . . . . : 10.0.0.2

C:\Documents and Settings\sidoh>ipconfig /all

Windows IP Configuration

        Host Name . . . . . . . . . . . . : muaddib
        Primary Dns Suffix  . . . . . . . :
        Node Type . . . . . . . . . . . . : Unknown
        IP Routing Enabled. . . . . . . . : No
        WINS Proxy Enabled. . . . . . . . : No
        DNS Suffix Search List. . . . . . : sidoh.org

Ethernet adapter Local Area Connection:

        Connection-specific DNS Suffix  . : sidoh.org
        Description . . . . . . . . . . . : NVIDIA nForce Networking Controller
        Physical Address. . . . . . . . . : 00-11-2F-62-A4-56
        Dhcp Enabled. . . . . . . . . . . : Yes
        Autoconfiguration Enabled . . . . : Yes
        IP Address. . . . . . . . . . . . : 10.0.0.199
        Subnet Mask . . . . . . . . . . . : 255.255.255.0
        Default Gateway . . . . . . . . . : 10.0.0.2
        DHCP Server . . . . . . . . . . . : 10.0.0.15
        DNS Servers . . . . . . . . . . . : 10.0.0.2
        Lease Obtained. . . . . . . . . . : Thursday, April 13, 2006 10:21:02 P

        Lease Expires . . . . . . . . . . : Friday, April 14, 2006 10:21:02 AM

C:\Documents and Settings\sidoh>
I suppose you could be right, since there is probably no one simotaneously doing TCP/IP releases/renews on either of the networks I deal with in large.

To elaborate on my point, though, DHCP does assign IP addresses by MAC addresses.  If the local computer (in reference) has a lease, it sends the DHCP server its MAC address, which is validated.  If the server verifies the existance of the lease, it assigns it the previously designated IP address (this is why none of the IP's on my network change, even though I've been using the same DHCP server for over a year).

[Eric]

Sidoh is correct.  Dynamic address allocation is based almost entirely on MAC addresses; that's why most internet routers have support for MAC address "cloning."  If your lease expires (or is manually released), however, your IP address can be taken by another host, so on devices where DHCP is more appropriate (laptops, for example), but you still wish to use static IP addresses, you'll have to set up dhcpd similar to how Newby has done.

[MyndFyre]

dhcpd (and every single other DHCP server I've worked with, including ones on multiple routers)assigns IP leases according to a MAC address.  If this weren't true, releasing and renewing in IP configuration utilities would result in new IP addresses, which, in my experience, is never the case.

DHCP servers assign leases to a certain MAC address.  They will only dismiss the leases when the expiration date rolls around or if they are manually dismissed by a systems administrator.

As Newby said, I have had the opposite experience.  The only reason the DHCP server reallocates the same IP address to me is that when I released it, it was freed.  My Linksys router regularly cycles through about 2 values more than computers I have.  It's irritating.

Sidoh is correct.  Dynamic address allocation is based almost entirely on MAC addresses; that's why most internet routers have support for MAC address "cloning."  If your lease expires (or is manually released), however, your IP address can be taken by another host, so on devices where DHCP is more appropriate (laptops, for example), but you still wish to use static IP addresses, you'll have to set up dhcpd similar to how Newby has done.

Well you'll forgive me if I don't take you as a, shall we say, industry expert, but I'm sure I could think of a reason to skip MAC address cloning.  One such reason would be in the event the DHCP server had a list of valid MAC addresses and you wanted to expand the network.  You remove one device, clone its MAC, and put the device that was cloned on the new router's private network.

Why would dynamic IP addresses be based on MAC addresses?  IMO they have absolutely nothing to do with one another.

[Sidoh]

As Newby said, I have had the opposite experience.  The only reason the DHCP server reallocates the same IP address to me is that when I released it, it was freed.  My Linksys router regularly cycles through about 2 values more than computers I have.  It's irritating.

Regardless of this of this fact, the IP address leases are based on MAC addresses (if this weren't true, the DHCP server would not know who's talking to it when a request is made; it'd be forced to assign you a new lease each time you restarted your computer).  I'm sure you can set some DHCP servers so you're reassigned a new IP address every time you query for one, but the MAC address of a network card plays an important role in DHCP transactions.

Why would dynamic IP addresses be based on MAC addresses?  IMO they have absolutely nothing to do with one another.

Because DHCP server assign IP address leases.

[iago]

DHCP may associate the same IP with the same MAC, but it doesn't have to.  For example, on Windows' DHCP server, I'm pretty sure the IP is randomized (I've gotten 192.168.0.221, 192.168.0.162, 192.168.0.64, and several others.. it's really weird)

Usually when I request a DHCP address, my system remembers the previous IP and requests it specifically.  Additionally, the router sometimes remembers IP:MAC mappings for a brief time (couple days, I think).  Between the two of those, the IP address often doesn't change.  But the point is that it CAN. 

[Sidoh]

DHCP may associate the same IP with the same MAC, but it doesn't have to.  For example, on Windows' DHCP server, I'm pretty sure the IP is randomized (I've gotten 192.168.0.221, 192.168.0.162, 192.168.0.64, and several others.. it's really weird)

If a lease has been granted, then yes, it does assign the machine the same IP address as long as that lease is not expired (or it has been manually/accidentally removed by an administrator/program bug).

Usually when I request a DHCP address, my system remembers the previous IP and requests it specifically.  Additionally, the router sometimes remembers IP:MAC mappings for a brief time (couple days, I think).  Between the two of those, the IP address often doesn't change.  But the point is that it CAN. 

I know they can, but if the DHCP server has assigned a lease and it's not facing a shortage of possible IP addresses in its specified range, it will assign the same machine the same IP address if the lease has not yet expired.

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        Lease Obtained. . . . . . . . . . : Friday, April 14, 2006 8:47:14 AM
        Lease Expires . . . . . . . . . . : Saturday, April 22, 2006 8:47:14 AM
If this weren't true, what would be the point of a lease?

[iago]

DHCP may associate the same IP with the same MAC, but it doesn't have to.  For example, on Windows' DHCP server, I'm pretty sure the IP is randomized (I've gotten 192.168.0.221, 192.168.0.162, 192.168.0.64, and several others.. it's really weird)

If a lease has been granted, then yes, it does assign the machine the same IP address as long as that lease is not expired (or it has been manually/accidentally removed by an administrator/program bug).

Usually when I request a DHCP address, my system remembers the previous IP and requests it specifically.  Additionally, the router sometimes remembers IP:MAC mappings for a brief time (couple days, I think).  Between the two of those, the IP address often doesn't change.  But the point is that it CAN. 

I know they can, but if the DHCP server has assigned a lease and it's not facing a shortage of possible IP addresses in its specified range, it will assign the same machine the same IP address if the lease has not yet expired.

Code: [Select]

        Lease Obtained. . . . . . . . . . : Friday, April 14, 2006 8:47:14 AM
        Lease Expires . . . . . . . . . . : Saturday, April 22, 2006 8:47:14 AM
If this weren't true, what would be the point of a lease?

That's fine and dandy, for that implementation.  As I said, there's no guarentees, DHCP isn't required to behave that way.  DHCP can change your IP whenever it feels like it (Windows' implementation, for example, does).  Static IP is the only way to be guarenteed the same IP.

[Sidoh]

That's fine and dandy, for that implementation.  As I said, there's no guarentees, DHCP isn't required to behave that way.  DHCP can change your IP whenever it feels like it (Windows' implementation, for example, does).  Static IP is the only way to be guarenteed the same IP.

For the period of time the lease isn't marked as expired, it is required to behave that way.  That was my original point.

I misunderstood Newby's original post, but I do say what he is saying.  I'm simply saying DHCP servers almost always assign IP addresses while concurrently reading/recording the MAC addrses of the client.  If it assigns leases (which is the case, by default; I spent 5 minutes configuring the Windows DHCP server and it assigned leases), it does deal with the MAC addresses.  You're correct, though, it doesn't guarantee that address for an undetermined amount of time.  It does, however, guarantee that address for the time that the lease is considered valid.

[iago]

Well, on Windows XP, I can request an ip, reboot, and request it again in less than 2 minutes, and the ip changes to another random value in the range of (2, 254).  Maybe it has a very short lease time?

[Chavo]

Well, on Windows XP, I can request an ip, reboot, and request it again in less than 2 minutes, and the ip changes to another random value in the range of (2, 254).  Maybe it has a very short lease time?

Or maybe the Windows device driver is broadcasting a different MAC