I see that you've had several suggestions on this problem, but none has
solved the issue for you.I can see your responses, but I can't see what
others have suggested, so I'm sorry if this path has already been
explored.
It seems that the problem is that the RV082 is using the DNS records
from it's WAN0 provider when it serves leases to your clients. (I'm guessing that the AT&T DSL line is primary, and Comcast is secondary, but it doesn't really matter which is which) If I'm right, then the RV082 will pick AT&T's DNS servers, and tell the connected computers to use those IP addresses for DNS lookups.
When the AT&T link goes down, the RV082 fails over to the Comcast link, but the client computers are still trying to hit AT&T's DNS servers.
AT&T of course doesn't want to serve comcast customers, so those packets are dropped on the floor by AT&T's routers.
After the failover, the RV082 will update it's own DNS to use the secondary WAN provider's DNS servers, which is why a DHCP renew will generally solve the problem for you.
If I'm right, then the real solution will be to use an ISP-neutral DNS service, so the client can connect to the DNS servers regardless of which ISP is currently in use.
Try configuring the RV082 to use static DNS server addresses: 8.8.8.8 and 8.8.4.4, rather than getting them from your ISP. Those are Google's public DNS servers, and you can read about them here.
I hope this helps, but if I'm just re-suggesting a previous suggestion, I'm confident you know how to re-open the question. :)
Best of luck
Hi Mark, I'm glad that my explanation made sense. I had inferred that someone had already said "make your own DNS server" and I appreciate that not ever organization can just spit out new servers at will.
I like the way you explained the DNS updates -- that your rv082 immediately switches its DNS servers, but clients don't learn about that change until a DCHP refresh.
I don't think there's a risk of data loss to try using Google Pubic DNS, but there is certainly a risk of internet connectivity loss, (the same headache you have when AT&T's WAN link goes down, and nobody can reach named hosts) and of course a proper test will involve pulling the AT&T jack out of the DSL router to verify that it functions through a failover.
All of those do argue for the IT person's favorite phrase -- off hours maintenance window.
There is some work that you could do prior to the test though -- configure one of your machines to use static DNS instead of DHCP, and confirm that it can use the Google Public DNS servers (8.8.8.8 and 8.8.4.4) without problems. That'll only verify the AT&T WAN connection, but it's a start.
Keep me posted if/when you get a chance to do some testing.
--Rob
Thanks for patiently wading through the folks who offered generic suggestions. I'm glad that you have ended up with a solution that works for you.
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Hi - I've been reading (well one side of the troubleshooting effort) and one item I'm not sure was covered is with your ISP's - Have you verified that your on static IP service with both providers. While their primary and secondary DNS servers address should not change - part of your problem could be when they refresh their IP address.
Another comment to the problem is why is your router having to fail over this frequently? I understand the frustration on this issue - in addition to getting a solid resolution - you really also need to look to the root cause of why the WAN has to keep flipping over from one ISP to the other.
And one comment made was true that a netowrk of your size should be operating with a Active Direcltry DHCP and DNS Server. I understand the expense concerns but this could be run on a robust tower machine with at least 4 gig or ram. Sorry this is not a solution - as from the one side I was reading aounds like Javaman was providing acurate troubleshooting
I would suggest you set up a local DNS server. An excellent choice might be to install a Windows Server 2003 machine & configure it as a DNS server.
You will then configure DNS on that server so that it forwards requests for domain name resolution to the DNS servers at both ISPs. You will then configure the DHCP server on the RV082 to distribute the IP address of this local DNS server as the preferred DNS server for the rest of the devices on your network.
This will ensure that DNS is not impacted when the failover occurs.
Http://ask-leo.com/i_cant_access_some_websites_why.html
also change the router mac address off of clone pc to a random one and that should help out too.
Can you explain your setup in more detail? If you are failing over to a different ISP , i.e. cable from T-1, then your DNS will indeed have to change. Where is your DHCP and DNS info coming from? A server, or the router? If it is from the router, when it kicks over to the failover, if you refresh your IP/DNS info does it give you the DNS from the secondary ISP? If you are using a server to handle DHCP/DNS, what OS is it?
The simplest thing to do in this scenario would be to manually assign the DNS server on the client PC's. I.e. let them get their IP dynamically, but set the primary DNS server as the Router (192.168.0.1 or whatever you have it set as). In this scenario, even if there is a failover, the client pc's will look to the router for DNS info, and not the passed through DNS info from the ISP that they get at first logon. Thus geting their DNS from whatever source the router is currently using successfully.
Wireless clients are more of a problem, but in the event that there is a switchover of DNS info, the wireless can be quickly turned off and back on.
It's not the most elegant solution, but the way windows clients behave, they get their DNS assignments, and until they are released/renewed they keep that assignment.
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Did you try re-configuring the router with settings recommended in the config manual. Just in case you don't have it you can download it from the link below
http://www.equinux.com/cms_components/us/products/vpntracker/media/files/HowTo_Linksys_RV042.pdf
Let me know if it worked.
Sai.
Checking the Router's LEDs
Step 1:
Make sure the System LED is lit.
NOTE: If the Diag LED doesn't goes off, you need to upgrade the router's firmware. For instructions, click here .
Step 2:
Make sure the LAN 1-8 ports is lit depending on the computers connected to the designated Ethernet port.
NOTE: If the LAN 1-8 port is not lit, make sure that the computer is powered on. You can also try connecting the PC using another working cable.
Step 3:
Make sure the Internet (WAN1) and DMZ/Internet (WAN2) LED is lit.
NOTE: If the Internet or DMZ/Internet LED is not lit make sure the Broadband modem is powered on and that the modem is properly connected to the Ethernet port
You can access the web-based user interface utility of the RV082 by using one of two methods:
1. Open a web browser (Internet Explorer or Netscape Navigator)
· By IP address: Type http://192.168.1.1 (192.168.1.1 is the default IP address of the RV082)
and click Go or press the [Enter] key.
· By Hostname: Type http://RV082 and click Go or press the [Enter] key.
2. When the username and password prompt appears, type admin in both the username and password fields. (admin is both the default username and default password for the RV082).
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You linked a VPN configuration guide, but my issue has nothing to do with VPN. For what it's worth, I did read the guide, but I saw nothing there that even remotely related to the problem at hand.
The issue remains unresolved.
The issue is that the router should handle the switch from primary WAN to backup WAN in a manner that is seamless and transparent to the connected computers and equipment. It is not acceptable to have to run around to every PC in the building to get them working again after an automatic fail-over. And then when the primary WAN becomes operational again, the router would then automatically switch again, necessitating more running around. Every time this happens there is a potential for data loss.
When I first installed the RV082, the fail-overs worked perfectly. Now, they do not. Not being an RV082 expert, I don't know if the problem is related to router configuration, firmware updates, or if it's just that Microsoft has imposed so many changes via Windows Update that XP now has a problem that Linksys did not anticipate.
I already called Linksys for support and they shuffled me off to Cisco. Unfortunately, Cisco refuses to provide free or paid support for any RV082 beyond one year, so I am left on my own.
This problem remains unresolved.
Can you explain your setup in more detail?
[MWS] Sure - the two ISPs are AT&T ADSL and Comcast Cable Modem. Each of these connects to one of the two WAN ports on the RV082 router. We use some static IPs for printers, access points, and such, but PCs, DVRs, NAS drives, AV receiver, PS3, and Vonage TAs get IPs via the DHCP server that is built into the RV082. The RV082 has direct connections to three Vonage TAs and a 16 port Netgear Etherswitch. The etherswitch feeds a Linksys DWL-2700AP access point and all of our wired network. We have a few smaller etherswitches in areas in high connection density, with a total of around 18 wired users and as many as 12 wireless users on the network. PCs are a mix of Windows XP and Windows 7.
If you are failing over to a
different ISP , i.e. cable from T-1, then your DNS will indeed have to
change.
[MWS] We use DSL as the primary and Cable modem as the secondary.
Where is your DHCP and DNS info coming from? A server, or the
router?
[MWS] DHCP comes from the the RV082 router.
If it is from the router, when it kicks over to the failover,
if you refresh your IP/DNS info does it give you the DNS from the
secondary ISP?
[MWS] If I release and renew the IP address at any given PC, it usually starts working again, but of course, I don't really want to have to be running around to every individual PC every time the RV082 does an automatic ISP change. And for what its worth, presumably dumber devices, like the AV receiver, PS3 and DVR all seem to handle the switch-over without any intervention on my part.
If you are using a server to handle DHCP/DNS, what OS is
it?
[MWS] No, we have a Windows XP Pro box that we use as a server, but it's not a domain server and it is not doing DHCP. All DHCP/DNS comes from the RV082.
Well, I'm sure that would work for desktop PCs, but it's not going to work for roaming notebooks or for wired devices that do not provide any way to manually specify DNS. And the fact that it will not work for wireless notebooks is no small point - we have experienced database corruption on more than one occasion because of this problem. I simply cannot afford to allow this to continue. That leaves me with no choices other than to disable the backup WAN feature or to do something to the router that will make it work again as it once did.
The fact that it used to work just fine makes it all the more frustrating - on at least two occasions, it worked so seamlessly that no one even knew that our DSL service had gone down. It wasn't until I happened to look in the equipment closet (at something else) that I noticed that the status lights on the cable modem didn't look normal.
That is the entire reason for the RV082 - to make it so that no productivity is lost when the Internet connection falters. If the RV082 actually causes a loss of productivity instead of preventing it, then it is a failed design. That might explain why Cisco refuses to support it beyond the first 12 months. I even considered buying a new RV082 just so that I could get Cisco support - I'd like to actually hear them tell me that it doesn't work with Windows.
A solution that does not cause data corruption has not yet been offered, so this issue must remain open.
Thanks for the idea, but the original RV082 setup did not clone any MAC addresses.
The default MAC addresses are 00-16-b6-4d-c0-c3 for WAN1 and 00-16-b6-4d-c0-c4 for WAN2, both of which resolve as Cisco-Linksys addresses.
This problem is yet to be solved.
Well...we may be able to justify the cost of purchasing, operating and maintaining a domain server at some future date, but at the moment I have to admit that it sounds like a lot of expense just to restore the functionality that we once enjoyed with the RV082 alone. Not to mention the extra space, the power bill to run another computer, and the impact on the environment. And I have no knowledge of what it takes to host a domain server...but I feel like it might create quite a bit of Internet traffic for us...the cache has to get updated somehow, right?
well...okay...but old DNS all of the time might be almost as bad as no DNS on rare occasions. I won't rule this out as an idea for some future date, but I don't think it's going to happen soon enough to be the solution to my router problem. And at some level, I just want the router to perform as advertised.
I think we need someone that has experience with this specific series of routers - the Linksys/Cisco RV042, RV082, or RV016.
I sure do appreciate your response JavaMan. I had no idea that both sides of the conversation could not be seen by all contributors. This really is an ironically awkward interface for problem solving.
AT&T is, in fact, the primary WAN. What you are saying seems logical to me. I would like to try your suggestion, but since there is a risk of data loss, I need to do it when I can get everyone else off of the LAN. My feeling is that the RV082 switches the DNS at the same time that it switches the ISP, but the Windows PCs ignore the new DNS until manually refreshed.
One of the previous suggestions was to set up my own DNS server, which is along the same line of thinking, although we cannot reasonably afford to purchase, install and operate a new server for the sole purpose of hosting our own DNS. But if the Google DNS servers are fast and reliable, that would certainly be doable.
I have to admit that I do not understand this interface, so I hope I am responding in a way that will keep you in the loop.
-Mark
I appreciate you taking the time to try to understand my specific needs rather than making generic suggestions that I could not reasonably implement.
The fail-over works perfectly when using Google's public DNS servers. I did notice some slowness tonight...I wonder if it could be that their servers get bogged down on the weekend. If this turns out to be a pattern, then perhaps I can find another ISP-neutral DNS server that I don't have to host in-house.
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