I just replaced my cable modem with a new Surfboard SB5120. I am getting drops in connectivity and see this error message in the modem logs:

IGMP: ERROR - Group address 0.0.0.1 is not a legal multicast

Can anyone shed some light as to what this means?

Thanks in advance.

Hmm, well you may need to notify your cable company of the cable modem's new MAC address. 'cause many such ISPs use that as of means of identifying "legal" customer connections.

i work for a cable company that uses moterola SB5100 and SB5101 i believe that your model is pretty close... you need to get your ISP to upgrade your firmware.

also are u using the ethernet connection or the USB connection, try the other and see what that does, if your ISP is like my company power cycling the modem should bring the new firmware... but if not you may need to get a new modem or make sure your ISP has activated it in thier system.

Also this DOCSIS modem has the ability to be a router, now i know my company disables this ability in the firmware, yours might not if you are allowed to log into the modem as you would a router and change some settings or manually update firmware if you are allowed.

Thanks for the quick responses, guys. I appreciate it.

I am using an ethernet connection like I had with my last cable modem. I have power cycled many times and that hasn't solved the problem. I am going to call the service techs when the problem happens again and see if they can't troubleshoot from there.

Thanks for the info.

@Taco: Like I have said before, this is THE place to assimilate knowledge.

ob1, have you been able to resolve this problem? I'm having the same problem atm

First off, welcome aboard xuphu! This is a wonderful place with helpful people that I can't say enough great things about them.

The problem was actually with my NIC card. I purchased a new one from Best Buy for 15 bucks, slapped it into my Dell, and I was good to go.

what model was your previous NIC and the one you bought?

Thanks in advanced.

My Dell came with a Realtek RTL8139 Ethernet NIC...Best Buy had the same exact model.

I'm so glad I found this thread. I'm having the same problem. Just before I typed this post I called up my ISP and they said everything seemed to be fine. I have some Kingston ethernet card that they gave me when I had my SV4200. I'll see if changing the connection from that to one of my mobo's onboard ethernet ports will do the trick.

Edit:

Unfortunately, my logs still give me this:

Map Reject - Downstream Traffic Flow Not Mapped to BPI+ SAID

DHCP WARNING - Non-critical field invalid in response

DHCP: Renew: Missing Syslog server

With the docsis 5100, 5101 and 5120 if you put the modems on stand by and you dont get a 192 address it is 99.9% of the time an issue your your system mainly your nic.

I work for a company called Shaw Cable in Canada and we use these modems... my job specificly is troubleshooting these kinds of issues in customers homes...

Hi, I have the same problem stated above.
this is my Log file:


My ISP so far have no clue of what the 0.0.0.1 is not a legal multicast error means. Therefore they cant help me.
I also mentioned to them about the software updates and they said they had none.

Im using a SBV5120 SURFBoard Cable Modem from Motorola.
My ISP is: Optimum Online (www.optimumonline.com)

And this is what it happens all the time:

1- My internet connection dies (i cant browse nor use any internet related programs)
2- My status signals stay all solid (they dont go off nor reset)
3- After 10-15 minutes my telephone dies (I have VOIP phone){Im still offline}
4- 1 or 2 minutes later my modem resets itself and Im back online and phone works again.

The right thing for a modem to do is to reset as soon as I loose internet connection, but thats not my case as stated above.

I also tried buying 3 other modems and my ISP replaced my modem 2x so far.
My cable line is brand new and all splits were removed.
I tried (test) this using a router and no router at all
I also tried (test) to connect my modem to 2 different computers (not at the same time)
And also did System restore in case it was a virus

So far my ISP still has no clue of whats going on.
So I was wondering if you guys have any idea of this consern.
Thanks.

what are your downstream and upstream power levels?

EDIT: I to run OOL+OV and am getting the same errors in the modem log. However I haven't been kicked off or anything. check out www.dslreports.com Cable Fourm and see if they talk about it there.

EDIT2: I posted in this thread so hope it helps out: http://www.dslreports.com/forum/remark,159...s=9999~start=20

your upstream level seems a bit high. the magic number for upstream is under 54. anything over and the modem won't work(so to speak.) if you are using any spliters try removing them and connect the modem directly to the line. remove any filters or boosters to, they don't do shit for modems. the best way to go about it is to split the line coming from the pole and run a dedicated line for the modem and split the other line for your TVs. If your modem still doesn't work off the original line-drop, call your cable company, they might have a shity amp on the pole.

EDIT: oh yea, btw, your IGMP error thing seems to be a Motorola issue. I have an SBV5120 VoIP modem.

*I thought I added this reply before... oh wellz*

My ISP still dont know what the issue is and promised me to change my modem to a white modem.

And after the visit yesterday from the ISP my power level went up from 47 average to 51 >.>

thanks for replies.

Here's a snapshot from my SB5100...



My father and I recently replaced all the cable lines in the house with higher grade coax. Also we made out cable company come out and replace the line from the pole to the house, and we ran ethernet cable through the whole house to make everything wired (except my sister's notebook).

Anything about 54 on the upstream will kill your connection. Ask your ISP to replace your outside line, also I removed all splitters on my line for the internet connection, we have satellite tv so we don't need cable anywhere else.

My connection is 10mbit for internet (actual internet, not network speed). So I can usually download around 1.5 - 2.0mbps. It's pretty sweet.

this is what I got.
I have Optimum Online Boost.
-3 seems a bit low considering you have a direct line to your modem but still a good signal. The magic number for downstream is between -15 and +15. The power levels go nuts around the summer time so a little downtime may be expected.

Actually -3 is better than your +7... 0 is the optimum level. Whatever is closer to 0 is better. (So my ISP tells me)... correct me if I'm wrong.

yea, +7 is kinda bad but the cable is split once before it hits the modem. So without the spliter the DS level would actualy be higher. I'm just saying that for an off-the-poll cable line the power level shouldn't even be in the negitives. I guess maybe this has something to do with you not having cable tv?

Yeah, I don't have cable tv, but everyone around here including my grand parents and some friends in town are all in the -'s. Our ISP has a limit each way of +13/-13. I remember when I had -14, the modem would barely stay connected. Removed all the splitters and replced lines, it's like going from 56k to fibre optic haha.

a white modem is little info to us... make/model and the reason it most likely changes is because if it is not a docsis it will be on a different frequency and then the signal will be different.

And despite what some people have said about the Docsis modems... here is what your lvls should be

down stream +7 to -7 is where it should be but the modem will work ok from +11 to -11 anything worse then that and you will have issues, That goes for the docsis VOIP modems as well.

upstream is 36 to 53, although a little above 53 will still work, anything below 36 and there is a big problem, but you have to consider your signal to noise as well... on a docsis you want it between 30-40 anything lower and your ISP has to change something on thier end.

now some ISP's will let the numbers go higher and lower then what i have stated but these are all where your ISP should aim for for the best signal and leaste amount of packet loss.

Hi again :-p

Ok, the "White modem" was a modem they used on the past.
I dont really know the version nor model of the modem so I cant provide much help.

Anyway, after having techs coming like 6x at my house after i posted here they still havnt changed the modem (to white one).
They do keep changing it to the SBV5120 though, but no fix yet.

They totally gave up on my issue, wich is sad (for me).
But the only thing im hoping on now is that whenver Optimum Boost is available on my area this problem is solved as well.

Another note:
They said the modem is running on its latests drivers/softwares, and I didnt find any update on it myself on the web.

The software versions Im using is:

i dont know if u stated this before but who is your ISP?

Hello there Kagerusui

I'm having exacly the same problem. next monday it's gonna be the 6th time for them to come. they replaced everything from modem to the cable that goes to the pole.

yesterday I had the Optimum Online Network guys sitting outside and monitoring the network here. they saw nothing. when later on the same evening, had the problems again, I called the support and they told me there's about 20% packet loss and that the transmit signal is low.
they will send someone again on monday, but until the technitian see the problem in realtime, he will not be able to fix it

it's been amonth now.

White modem = Surfboard 4100 (or around that model number). And it's not going to fix your problem.

white modem may fix the problem.. if its the one im thinking off it operates on a different frequency, different routers with different firm ware... so unless the issue is with the cable only it will fix it... but if its with the ISP routers and software it will most liekly fix the issue. well if u can call that fixed.


if the white modem looks somewhat like this and a little bigger and white and only has 3 lights it is the one i am thinking of.

It won't fix it because it's not a modem issue. The sb5100 was replaced many times and that did not fix the issue, anyways the white modem that the company is talking about is most likely this modem:

I have the same Problem with my Motorola SBV5120E
could anybody find a Solution for the IGMP: Error etc...?

I have big problems with my Internet and telephone, the speed is sometimes good and then too slow. Sometimes I can`t surf and get an error in the internet Page.


Could anybody help me?

I have done three cap from my Problems.

1) CAP from my Log (IMGP: Error Group Address 0.0.0.1 ist not a legal Multicast)



2) CAP from my SIGNAL:



3) Cap from my STATUS:
[img=http://img214.imageshack.us/img214/7607/statusmodemsbv5120emotoroladq3.th.jpg]



Thanks in advance

i couldn't get a pic of the modem you pointed to but the reason i said the white one might fix it is because if the white modem does not use the DOCSIS network any problems affecting the DOCSIS network of our ISP will not affect a non DOCSIS modem






Your signal looks fine, you seem to be getting some packet loss. It looks like you are using a VoIP/Internet DOCSIS modem, you may be getting issues because they are on the same modem, some ISP's use this VoIP modem for Phone only and then use a SB5100 for internet, this is costly for the ISP but the ideal way to go as then your internet and phone dont need to share the same channel and bandwidth.

The modem does not need the time to work but without the correct time your log files will be off, and can cause iissues, i suggest a modem swap and a call to your ISP

Hi Everyone. I've been struggling with my Cable Company and my many routers that I have purchased (3 to be exact). I'm using a Surfboard 5120 Motorola modem that my cable company has provided me and a Netgear Wireless G router and I CAN'T GET MY CONNECTION TO STABILIZE WITH ONE OF MY ROUTER CONNECTED TO IT. I have called my cable company and they say it's the router... so I called my router's 1-800 number and they say it's my cable company.
I'm getting a:
"IGMP: ERROR - Group address 0.0.0.1 is not a legal multicast"
message when I log into my modem's IP Address. I've never seen this message before unless the router was failing but now I'm seeing it all the time, even without the router connected to the modem and I'm still ABLE to access the internet too. However, this is not the case when I connect the router in series with modem. I've also checked all of my signals and they are fine:

Downstream...............................Value
Frequency................................687000000 Hz
Signal to Noise Ratio....................35 dB
QAM......................................QAM256
Network Access Control Object............ON
Power Level..............................-4 dBmV


Upstream.................................Value
Channel ID...............................4
Frequency................................31000000 Hz
Ranging Service ID.......................2741
Symbol Rate..............................2.560 Msym/s
Power Level..............................43 dBmV

I don't know what to do and I don't know who to believe but I can't access the internet via my router only through my modem and I don't know why.
PLEASE HELP!!!

I am Having the same problem. After reading this form I checked my NIC and got the correct IP address. I am using a motorola sb5120 for the last 7 days. Before that I had a Sientific Atlantic with the same problem. I have asked my ISP provider about firmware but they did not do that. I get two DHCP Erors then I get the IGMP error every hour on the hour. I have had them replace the line from the house to the box. to bring my noise levels to their spec.

Downstream Value
Frequency 687000000 Hz
Signal to Noise Ratio 37 dB
QAM QAM256
Network Access Control Object ON
Power Level 7 dBmV The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading


Upstream Value
Channel ID 3
Frequency 30000000 Hz
Ranging Service ID 740
Symbol Rate 2.560 Msym/s
Power Level 47 dBmV