WAP54G firmware upgrade goes awry

Yes, I'd say so. You just destroyed two routers.

Don't feel bad, I did exactly the same thing last week. Fortunately, I got a replacement router from Linksys.

If you're going to flash-upgrade, do it from a directly ethernet-cable-linked box with nothing going on with the router while it's happening.

Try it otherwise and you're almost certain to wreck the router.

Good luck!

-=- This message was sent via two or more anonymous remailing services.

On 19 Jun 2006 07:56:03 -0000, Anonymous wrote: : Robert Coe writes: : : > Is this a known problem? : : Yes, I'd say so. You just destroyed two routers. : : Don't feel bad, I did exactly the same thing last week. Fortunately, I got a replacement router from Linksys. : : If you're going to flash-upgrade, do it from a directly ethernet-cable-linked box with nothing going on with the router while it's happening. : : Try it otherwise and you're almost certain to wreck the router. : : Good luck!

Thanks for the well-intentioned advice, but you evidently didn't read anything but the subject line of my article.

1) I didn't destroy the routers (access points, actually); they were fine (and correctly updated) after I restored them to factory settings.

2) They were hard-wired to the Ethernet, as was the computer I used to update them. I've updated dozens of routers and access points that way.

3) If an access point is turned on, you can't ensure that there's "nothing going on" if there are wireless clients nearby. (If it isn't turned on, you can't update it.)

As I said, thanks anyway.

Bob

I did the same firmware upgrade about a month ago. WAP54G hardware version 3.0. Firmware went from 2.06 to 3.04. No problems. However, the upgrade did not retain any of the settings. I had to reset the access points to defaults and reload everything.

Ummm... did you do it via wireless or wired from the other building? If wireless, I've had a few disasters trying to do it over wireless. The problem is that the firmware overscribbles parts of the running firmware needed to finish the firmware upload. It initiates a disconnect or possibly a reboot before the upload is completed. This does not happen with a wired ethernet connection.

If done from another building, how many feet of CAT5 were involved? I'm not sure I would trust hundreds of feet of cable to deliver the firmware without any errors.

I've noticed that some routers and access points are very reluctant to display the internal web server. My usual trick is to tack on the "/" at the end of the URL as in: http://192.168.1.245/which seems to work better. Even so, it sometimes takes about 30 seconds for the login box to appear.

Also, I'm having a new problem with a different pair of WAP54G v3.1 (firmware 3.04) access points in bridge mode. If I make any change to the wireless config going through the wireless link from the other end of the bridge, the remote end of the bridge hangs or goes comatose until the power is cycled. It's quite consistent in both directions. It doesn't exactly fit your description but this might be what you're seeing.

Settings are not retained between major firmware releases (i.e. 2.x to

3.x). I don't recall if it cleared the settings (reset to default) or if I had to do it manually. As a matter of habit, I always reset a router to default after each firmware update (unless the instructions claim that the settings are retained).

Could you explain what you mean by "swapping them out"? If you have a large number of these, just prepare an upgraded access point, load the desired settings, and replace the access point with the pre-loaded upgraded access point. Don't bother trying to do field upgrades.

Also, note that reloading previously saved settings (config.dat) doesn't work between radically different firmware updates.

Incidentally, the subject should really be "WAP54G settings go away with firmware upgrade." The upgrade was apparently successful. Only the settings were lost.

On Sun, 18 Jun 2006 14:52:25 -0400, Robert Coe wrote in :

1. Never ever upgrade firmware over wireless. Use wired.
2. Always always save settings before any upgrade.
3. It's a good idea to reset the router to factory defaults after upgrade, and then load the saved settings.

On Tue, 20 Jun 2006 05:01:03 GMT, Jeff Liebermann wrote in :

Depends on the brand (and model) -- well engineered products (e.g., SonicWALL) can be restored that way.

From the way you've described the situation it seems clear the firmware upgrades between the two depend upon different configuration data. That's inconvenient, to say the least, but at least it's not a permanent failure issue. Best to get a spare, configure it as desired and physically swap the units in the field instead of trying to do an in-place, over-network upgrade. It would be nice if they'd warn you of this possibility, does the README give any clue?

On Fri, 23 Jun 2006 07:13:37 -0400, "Bill Kearney" wrote: : From the way you've described the situation it seems clear the firmware : upgrades between the two depend upon different configuration data. That's : inconvenient, to say the least, but at least it's not a permanent failure : issue. Best to get a spare, configure it as desired and physically swap the : units in the field instead of trying to do an in-place, over-network : upgrade.

Well, yeah, so it seems. But most of those access points are in inconvenient locations, and swapping them out is a pain. After all, not having to do that is why you want to manage such devices remotely. Let's just say that my opinion of Linksys hasn't gone up as a result of this experience.

: It would be nice if they'd warn you of this possibility, does the : README give any clue?

I'm too lazy to look it up, but I think not. I'm pretty sure I'd have noticed.

Would it be possible to do a factory reset on them in software before upgrading them, and then reconfigure them after the upgrade?

You'd have to make sure they'd still fit your existing subnet and not collide after the reset, but it might be easier than swapping them out.

On Mon, 26 Jun 2006 07:00:17 -0400, William P.N. Smith wrote: : Robert Coe wrote: : >most of those access points are in inconvenient : >locations, and swapping them out is a pain : : Would it be possible to do a factory reset on them in software before : upgrading them, and then reconfigure them after the upgrade? : : You'd have to make sure they'd still fit your existing subnet and not : collide after the reset, but it might be easier than swapping them : out.

If I did the factory reset first, I would not be able to talk to them again.

BTW, contrary to what somebody said earlier, it's not the case that doing the upgrade reset the router to factory specs. It merely made it unusable until I reset to factory specs and reconfigured.

On Sun, 18 Jun 2006 14:52:25 -0400, Robert Coe wrote: : The other day I upgraded the firmware on one of my Linksys WAP54G access : points from 2.08 to 3.04. I did it remotely from a PC in another building. All : went well until the upgrade was declared complete, whereupon the access point : became totally unresponsive. It continued to serve wireless clients, but could : not be managed. Even manually rebooting didn't help. I finally had to swap it : out, reset it to factory settings, and reconfigure it from scratch. (The : upgrade did "take"; the displayed firmware level is now 3.04.) : : Just to make sure it wasn't a fluke, I did the same thing to another WAP54G : over the weekend, from home. Now I can't contact that one either, so I guess : I'll have to swap it out tomorrow and reconfigure it from scratch. : : Is this a known problem? Is there a workaround (installing an intermediate : upgrade, for example)? I've got about a dozen more WAP54Gs I'd like to : upgrade, and swapping them all out would be a pain. : : Bob

Just on the off chance that anyone is still interested, I finally figured out the answer to this problem. The upgrade changes some, but not all, of the AP's settings. The critical one changed is the default gateway, which is set back to 192.168.1.1, even if the AP is set to get its IP settings via DHCP. So if you're trying to manage the AP from a computer on a different subnet, the upgrade causes the AP to lose the ability to respond to your commands, because it can no longer find you. A reboot doesn't help; all you can do (short of a reset to factory settings and full reconfiguration) is to log into a computer on the right subnet, set the AP to a static IP, change the default gateway to the correct value, and then set it back to DHCP. Damn.

On Thu, 29 Jun 2006 21:17:30 -0400, Robert Coe wrote in :

The gateway isn't a factor in the browser interface, which is actually just its LAN (as compared to WAN) address. The gateway is for routing traffic off the subnet; e.g., to the Internet.

Also, DHCP (client) has no bearing on this, since that's used to set the WAN (not the LAN) address.

Finally, the router doesn't need to "find you" -- you need to find the router.

My guess is that the LAN address is what's being changed, so you aren't able to access it at the old LAN address. If you know the new LAN address, use that, manually configuring the PC to the same subnet temporarily if necessary.

On Fri, 30 Jun 2006 01:59:22 GMT, John Navas wrote: : On Thu, 29 Jun 2006 21:17:30 -0400, Robert Coe wrote in : : : : >On Sun, 18 Jun 2006 14:52:25 -0400, Robert Coe wrote: : >: The other day I upgraded the firmware on one of my Linksys WAP54G access : >: points from 2.08 to 3.04. I did it remotely from a PC in another building. All : >: went well until the upgrade was declared complete, whereupon the access point : >: became totally unresponsive. It continued to serve wireless clients, but could : >: not be managed. Even manually rebooting didn't help. I finally had to swap it : >: out, reset it to factory settings, and reconfigure it from scratch. (The : >: upgrade did "take"; the displayed firmware level is now 3.04.) : >: : >: Just to make sure it wasn't a fluke, I did the same thing to another WAP54G : >: over the weekend, from home. Now I can't contact that one either, so I guess : >: I'll have to swap it out tomorrow and reconfigure it from scratch. : >: : >: Is this a known problem? Is there a workaround (installing an intermediate : >: upgrade, for example)? I've got about a dozen more WAP54Gs I'd like to : >: upgrade, and swapping them all out would be a pain. : : >Just on the off chance that anyone is still interested, I finally figured out : >the answer to this problem. The upgrade changes some, but not all, of the AP's : >settings. The critical one changed is the default gateway, which is set back : >to 192.168.1.1, even if the AP is set to get its IP settings via DHCP. So if : >you're trying to manage the AP from a computer on a different subnet, the : >upgrade causes the AP to lose the ability to respond to your commands, because : >it can no longer find you. A reboot doesn't help; all you can do (short of a : >reset to factory settings and full reconfiguration) is to log into a computer : >on the right subnet, set the AP to a static IP, change the default gateway to : >the correct value, and then set it back to DHCP. Damn. : : The gateway isn't a factor in the browser interface, which is actually : just its LAN (as compared to WAN) address. The gateway is for routing : traffic off the subnet; e.g., to the Internet.

Well, ah, no. The WAP54G is an access point, not a router. It has only one address.

: Also, DHCP (client) has no bearing on this, since that's used to set the : WAN (not the LAN) address.

See above.

: Finally, the router doesn't need to "find you" -- you need to find the : router.

I (well, my computer) knew where the access point was. But the AP couldn't respond because its gateway address was guffed.

: My guess is that the LAN address is what's being changed, so you aren't : able to access it at the old LAN address. If you know the new LAN : address, use that, manually configuring the PC to the same subnet : temporarily if necessary.

Your guess is a bit wide of the mark, but thanks anyway.

On Fri, 30 Jun 2006 20:49:03 -0400, Robert Coe wrote in :

Read what I wrote more carefully. The gateway address isn't relevant. That 'one address' is just the LAN address of its browser interface.

Ditto.

Not really. The AP is just a bridge, which knows nothing about gateways. It simply responds to the address that made the connection to its browser interface.

Since you know it all, I won't waste any more time trying to help.

Have a nice day.

Ah, I see where the confusion is coming from! You were updating it using the wired interface, but you were on a different subnet (on the other side of some other router), and when it set the default gateway back to 192.168.1.1 it couldn't talk to you any more.

Looks like you'll have to update the WAPs from the subnet they are on and then reconfigure them from there, yes? Hopefully it's easier to hook into their subnets than to replace them...

Thanks for the heads-up on this, BTW, I've got a couple of WAPs to update that are in _really_ inaccessable locations, and knowing the gotchas is going to help a lot!

On Sat, 01 Jul 2006 08:11:12 -0400, William P.N. Smith wrote: : Robert Coe wrote: : >I (well, my computer) knew where the access point was. But the AP couldn't : >respond because its gateway address was guffed. : : Ah, I see where the confusion is coming from! You were updating it : using the wired interface, but you were on a different subnet (on the : other side of some other router), and when it set the default gateway : back to 192.168.1.1 it couldn't talk to you any more.

Yes, exactly.

: Looks like you'll have to update the WAPs from the subnet they are on : and then reconfigure them from there, yes? Hopefully it's easier to : hook into their subnets than to replace them...

The WAPs' own subnets are a little less accessible than the one I was trying to use, but that solution is certainly simpler than going to several other buildings, finding the janitor to let me into the wiring closets, etc.

: Thanks for the heads-up on this, BTW, I've got a couple of WAPs to : update that are in _really_ inaccessable locations, and knowing the : gotchas is going to help a lot!

Well, I'm glad I posted the solution! I almost didn't, since I thought people might be tired of hearing me whine about it.

What kept me from seeing the issue clearly from the beginning was that only some of the AP's settings got reset. The instructions didn't say that could happen, and no Linksys upgrade has done that to me before. I probably would have realized what was happening a lot sooner if, as John Navas proposed, the AP's own IP address had gotten reset, but it didn't. In fact I believe the AP was still querying the DHCP server correctly; it was just ignoring the gateway address the DHCP server gave it. Very strange behavior.

Bob

On Sat, 01 Jul 2006 09:33:14 -0400, Robert Coe wrote in :

Access points (unlike routers) don't query DHCP servers because they don't care about IP addresses. They are simply bridges that just pass data link layer traffic back and forth, including DHCP traffic from clients talking to DHCP servers on the other side of the bridge. The management interface address of the access point is set manually, not by DHCP.

On Sat, 01 Jul 2006 16:26:53 GMT, John Navas wrote: : On Sat, 01 Jul 2006 09:33:14 -0400, Robert Coe wrote in : : : : >What kept me from seeing the issue clearly from the beginning was that only : >some of the AP's settings got reset. The instructions didn't say that could : >happen, and no Linksys upgrade has done that to me before. I probably would : >have realized what was happening a lot sooner if, as John Navas proposed, the : >AP's own IP address had gotten reset, but it didn't. In fact I believe the AP : >was still querying the DHCP server correctly; it was just ignoring the gateway : >address the DHCP server gave it. Very strange behavior. : : Access points (unlike routers) don't query DHCP servers because they : don't care about IP addresses. They are simply bridges that just pass : data link layer traffic back and forth, including DHCP traffic from : clients talking to DHCP servers on the other side of the bridge. The : management interface address of the access point is set manually, not by : DHCP.

That paragraph is, quite simply, bullshit. The most charitable comment I can manage is that Dr Navas must never have had the opportunity to read the user's manual of a WAP54G, the type of access point at issue in this discussion. (BTW, John, it's available on the Linksys Web site.)

John Navas hath wroth:

I beg to differ. Although the default setting is usually a static IP address, most access points allow the IP address to be set via DHCP.

For example:

DLink DWL-2100AP:

DLink DWL-7100AP: Dlink DWL-900AP+: Sorry, no Linksys examples until comes back. My foggy memory seems to vaguely recall that these also support IP address setting via DHCP.

The problem is what to do about the gateway IP address. Note that the default value for the gateway on the above examples is blank or

0.0.0.0 which means no default gateway. That makes sense as you would not want your return packets going off to the internet when they should be going to whatever IP is originating the packets. The only time one needs a real gateway IP is when the access point needs to get or send something to or from the internet. That can be time sync, update checks, logging output, and possibly DNS lookups. Otherwise, no gateway is required or desired.

Another uncommon problem is what to do if the gateway IP address happens to be outside of the netmask IP address range. This can happen if the LAN is divided into subnets. All current desktop OS's support this, but it seems to be lacking in commodity routers and access points. It's not a big problem but should be consdered for complex network topologies. (The easy solution is to alias the internet gateway router with a LAN gateway IP in each sub-net).

On Sat, 01 Jul 2006 12:50:31 -0400, Robert Coe wrote in :

I stand corrected -- the WAP54G can have the address of its management interface set by DHCP. However, that won't necessarily be helpful, since it won't necessarily be on the same subnet, which is of course the symptom described by the OP.