# CCK alternate IP... why, who, how?



## jes (Apr 21, 2007)

I am using a CCK to provide conectiviy on one of my HR20s... While debuging an unrelated network problem, I noticed that the CCK has a Secondary IP address.  Why? Who configured it & how can I change it?

Bridge Status
Model Number : DCAW1R0-01
Serial Number : XED3A1152A****
System Firmware Version : DECA-W-J715-V0.026S-T004
Wireless Firmware Version : 3.1.0.11.14.WNC.1.1.exported.PcieG3.Release
MoCA Firmware Version : EN2210.2.7.2.31

MAC Address: 90:A4E:97:nn:nn
Bridge IP Address: 192.168.13.2
Subnet Mask: 255.255.255.0
Secondary IP: 192.168.13.100
MoCA MAC Address: 90:A4E:97:nn:nn

Apparently the CCK assgined this IP blindly as my network printer is already using that IP! :scratchin

I configed the CCK, as well as all DirecTV recievers with static IPs...


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## dennisj00 (Sep 27, 2007)

Your router's DHCP server gave out that address. You can go into the GUI and re-assign the IP. More importantly, I would assign a static to the Printer outside of the DHCP pool.


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## HoTat2 (Nov 16, 2005)

dennisj00 said:


> Your router's DHCP server gave out that address. You can go into the GUI and re-assign the IP. More importantly, I would assign a static to the Printer outside of the DHCP pool.


But I guess the question is , why?

If the CCK-W is set to use a static IP (as "primary?"), it still pulls another IP address via DHCP from the router as a "secondary" though sets it as inactive.

Is the secondary IP assignment necessary to help speed a changeover to DHCP if necessary or something?


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## dennisj00 (Sep 27, 2007)

Interesting. . . I pulled mine out of storage and fired it up. The Secondary address is a 169.254.x.x address - which I would expect. Same firmware versions.

There's no place in the GUI to change it. My primary is static.


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## jes (Apr 21, 2007)

dennisj00 said:


> Your router's DHCP server gave out that address. You can go into the GUI and re-assign the IP. More importantly, I would assign a static to the Printer outside of the DHCP pool.


no it didn't. the Secondary IP was assigned by the CCK. My router's DHCP range is ...13 - ...99. My printer is static.

sorry I used alternate & Secondary interchagably in my original post. I corrected that, but can't change the thread title...


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## dennisj00 (Sep 27, 2007)

I don't know of any device that can assign it's own address - particularly with a .13.x . . . the 169.254.x.x are built in along with the MAC address at the factory. Some have a default address from the factory for further programming but it's usually a 192.168.0.x or 192.168.1.x address.


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## jes (Apr 21, 2007)

dennisj00 said:


> I don't know of any device that can assign it's own address - particularly with a .13.x . . . the 169.254.x.x are built in along with the MAC address at the factory. Some have a default address from the factory for further programming but it's usually a 192.168.0.x or 192.168.1.x address.


You can assign _any_ valid fixed address to a router, etc. Simplier devices will assign addresses for DHCP in the same IP block. Private network IP blocks are defined for IPv4 & IPv6 address space. Only private address blocks should be used for most home use. More sophisticated routers/firewalls can assign DHCP to blocks outside the block the management address is in...

example valid router addresses vs DHCP for the average consumer router/firewall, where xxx is 0-254, never including the router LAN IP address:

router DHCP range
192.168.0.1 192.168.0.xxx-192.168.0.xxx
192.168.13.13 192.168.13.xxx-192.168.13.xxx
10.10.10.100 10.10.10.xxx-10.10.10.xxx
172.16.69.42 172.16.69.xxx-172.16.69.xxx

The block 169.254.0.0/16 is a _link-local address_. I would expect to see an addres in that range when a device fails to get a DHCP address or if the CCK were talking to a device connected to it via Ethernet or Coax... sort of a device personal address.


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## dennisj00 (Sep 27, 2007)

Trust me, I understand router addressing. I even use 192.168.10.x, mainly to avoid conflicts when I VPN into other locations.

I've had my cck-w connected all afternoon and the secondary address hasn't changed from 169. It is a fall back address that can be used, in fact, your DVRs can be connected by only a switch or a single cable back to back and have MVR with the 169 addresses.

They're burnt into ROM at the factory- and generally never used other than for initialization or configuration.

I still don't understand why the secondary address got assigned to your device.

Maybe some others can check theirs and report in.


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## HoTat2 (Nov 16, 2005)

Dennis;

When I was trying to research this issue last night, I came across a short thread from Feb. of last year where you and VOS mentioned also getting a 192.168.x.x secondary IP address on your CCK-Ws at the time.

http://www.dbstalk.com/topic/191913-direct-tv-cinema-kit-connection-issue/

You didn't specifically state the exact numbers in the 192.168.x.x range you got, but VOS' was "192.168.1.64," but he said it behaved the same as a "169.254.34.156" (APIPA) address. 

Ever figure out why this happened?


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## harsh (Jun 15, 2003)

dennisj00 said:


> I don't know of any device that can assign it's own address - particularly with a .13.x . . . the 169.254.x.x are built in along with the MAC address at the factory. Some have a default address from the factory for further programming but it's usually a 192.168.0.x or 192.168.1.x address.


The 169 addresses are assigned in Windows OS software (except for Windows NT) absent being able to negotiate a DHCP assigned address. APIPA was a brainchild of Microsoft to deal with users who were running single link networks (crossover cables). Other companies have adopted this "standard" for situations where DHCP is not active.

http://tools.ietf.org/html/rfc3927


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## dennisj00 (Sep 27, 2007)

HoTat2 said:


> Dennis;
> 
> When I was trying to research this issue last night, I came across a short thread from Feb. of last year where you and VOS mentioned also getting a 192.168.x.x secondary IP address on your CCK-Ws at the time.
> 
> ...


My secondary was a 169.x.x.x address. VOS's was assigned DHCP by using the Ethernet port.

You can only use one. . . either the wifi connection or the Ethernet connection.

And if I browse to the 169. address, it goes to the primary :8080.


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## dennisj00 (Sep 27, 2007)

harsh said:


> The 169 addresses are assigned in Windows OS software (except for Windows NT) absent being able to negotiate a DHCP assigned address. APIPA was a brainchild of Microsoft to deal with users who were running single link networks (crossover cables). Other companies have adopted this "standard" for situations where DHCP is not active.
> 
> http://tools.ietf.org/html/rfc3927


It must have been a pretty good standard since everybody else now uses it.


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## HoTat2 (Nov 16, 2005)

dennisj00 said:


> My secondary was a 169.x.x.x address.


Oh OK,

Thought like VOS you had a 192.168.xxx.xxx address listed as that "secondary" IP too ...



> ... VOS's was assigned DHCP by using the Ethernet port.
> 
> You can only use one. . . either the wifi connection or the Ethernet connection.


That's what you suggested in that thread, but VOS claimed he wasn't using the CCK-W's ethernet port, but in the coaxial pass-through option.

But no matter, its no big deal I guess.


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## dennisj00 (Sep 27, 2007)

dennisj00 said:


> You can only use one. . . either the wifi connection or the Ethernet connection.


I take the above back! There was a time that I was using the WCCK as the connection from the DECA cloud back to the router AND Ethernet to one of my HR20-700s in the MBR.

My comment about one or the other refers to the connection back to the router, either wifi or wired.


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## jes (Apr 21, 2007)

I give up... :bang arp shows the CCK MAC for the Secondary IP of 192.168.13.100, not the printer's. Rebooted the router & CCK, no change. Changed the IP of the printer & arp now shows both IPs with their respective MAC address and the printer again shows in the router's attached device list. THIS IS A BUG on the CCK, not sure how to report it, but no network device should be assigning an IP without looking... :blackeye: Maybe this is the cause of some of the other CCK network problems posted... anyone?... anyone?... Bueller?...


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## Laxguy (Dec 2, 2010)

I was a fan of assigned IPs, but no more. In my new house, I've been letting the router do what it will, and have no problems associated with IPs for the last six months. OTOH, I have a max. of two dozen devices which look for a connection.


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## jes (Apr 21, 2007)

Laxguy said:


> I was a fan of assigned IPs, but no more. In my new house, I've been letting the router do what it will, and have no problems associated with IPs for the last six months. OTOH, I have a max. of two dozen devices which look for a connection.


In theory DHCP is a great idea... in implementation it generates overhead for the router & network... :eek2: The 2 devices that weren't happy playing together in this case were the CCK & an HP printer.

The HP printer should be static if you have Windoze machines on the network. Windoze creates a virtual port based on the IP address. While I rarely use or print from Windoze, I don't want to configure the printer everytime I do...

The CCK can't cope with DHCP overhead. When I initially set it up with the defaults as the WiFi link to an HR20 I moved to a room w/o Ethernet, you could not watch some HD programs *from* that HR20 (as server). There were severe audio & video dropouts. When I changed all IPs to static, the HR20 now behaves as it did when it was connected via Ethernet. I even had to change the HR20 from a reserved DHCP to a static IP.


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## Laxguy (Dec 2, 2010)

jes said:


> The CCK can't cope with DHCP overhead. When I initially set it up with the defaults as the WiFi link to an HR20 I moved to a room w/o Ethernet, you could not watch some HD programs *from* that HR20 (as server). There were severe audio & video dropouts. When I changed all IPs to static, the HR20 now behaves as it did when it was connected via Ethernet. I even had to change the HR20 from a reserved DHCP to a static IP.


You have struck a chord here, at least with me. When I mothballed my HR20 was about when I moved and set up with Genies, with direct ethernet cable to the HR34. At that time I went to all "no static" IPs. My HR20 was always on a fixed IP, as were my HR24 and H25s. Perhaps that is relevant to some reading here.


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## zebra (Nov 26, 2014)

Laxguy said:


> You have struck a chord here, at least with me. When I mothballed my HR20 was about when I moved and set up with Genies, with direct ethernet cable to the HR34. At that time I went to all "no static" IPs. My HR20 was always on a fixed IP, as were my HR24 and H25s. Perhaps that is relevant to some reading here.


So if you are all DHCP - how do you forward ports to specific IP. Does you router have a way of using device names instead of IP's, and thus have sort of dynamic port forwarding? What brand model is it? Or you simply do not have any need to access a device from WAN?


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## peds48 (Jan 11, 2008)

zebra said:


> So if you are all DHCP - how do you forward ports to specific IP. Does you router have a way of using device names instead of IP's, and thus have sort of dynamic port forwarding? What brand model is it? Or you simply do not have any need to access a device from WAN?


DHCP reservation.

Sent from my iPhone using Tapatalk


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