MSM760/MSM422 Network advice needed

[DennisCThornton]

I support a hotel that has a wireless & wired network set up for its guests.  This network was designed/installed and supported by a 3rd party vendor.  The setup consists of a MSM760 and about 18 MSM422 access points for the wireless and various switches for the wired.  Access points are powered via POE from the Cisco 3750G switches they're connected to. This feeds through a Cisco 2800 router to our main Cisco 3825 (ISP provided & managed) router to a DS3 line.   The 3825 also feeds the office network (all wired).

Network speed for the guest network is capped at 8MB global and 1MB per user.  Usage report show we peak @ 9MB occasionally. (vendor cannot explain why we can go to 9MB when capped at 8MB).

Site surveys show signal strength is ok with only a couple of weak spots.

Guests are complaining of poor wireless connectivity and dropped connections.  The vendor's response to customers when they call to complain is to reset the access point. 

My question is - Is this normal for this equipment in this type of environment?    If not, what should I be telling the vendor?  Will increasing the 8MB to 10MB improve wireless connectivity (as the vendor claims then admits it won't when pressed)?

[Arimo]

Hi Dennis

I certainly hope that "vendor" above refers to the people who installed the wireless!

Of course poor connectivity and dropped connections aren't normal or wanted. And while resetting an AP may be an intermediate workaround, it's not a solution. While I don't have an answer to you why the cap is occassionally extended, increasing the cap won't affect the connectivity. 

One thing you could do is play around with the AP transmit performance. Running them @ 100% transmit power isn't necessarily a good idea.

First thing here is to establish whether or not you're dealing with a wireless or wired issue.

What exactly means "poor connectivity" or "dropped connection"? Do the users have problems associating with the APs in the first place, or are they able to associate with an AP but experience poor throughput? Does dropped connection mean that user loses Internet connectivity, or that the client disassociates with the AP?

Do you see a lot of port toggling on ports connecting to the APs?

Do you experience same problems with all configured VSC:s / VLANs, or only one / some of them?

Has anyone done an on-site survey which would show also possible interference in the wireless space? Are the problems more apparent with APs which are placed in proximity of radio-controlled doors or other similar devices? All these (and more) can cause disturbance in wireless, which you can only find out with a proper spectrum analyzer - InSSIDer or similar tool won't reveal this.

Are the APs configured for dynamic channel mapping, or are the channels static? If they are static, do they follow the 1-6-11 or 1-7-13 -convention? If dynamic, do you see much channel hopping in the logs? This is another thing which you can test - configure strict static 1-6-11 or 1-7-13 -channel configuration to prevent overlapping and see if this improves the situation.

Are the problems more apparent with certain clients (for example Apple or smartphone) or are they completely independent of client type? Are they maybe more apparent at certain times of the day? Are they more apparent when there are more users in the wireless network?

Are the problems equally apparent with 2.4GHz and 5GHz ranges?

If channel configuration or transmit power doesn't have effect, I'd suggest is get answers to these questions (as far as possible) and collect the following:

- from controller filtered and unfiltered logs, configuration and sysinfo.bin -file

- a detailed physical network topology showing the devices, their IP addresses and interconnecting port numbers

- site survey results

- a floor map of the site showing AP placements, their channel configuration and distances.

Then get in contact with your local support center.

Of course you could check the Implementation Guide (http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c02682324/c02682324.pdf), scrap the current config and implement the Hospitality solution from there. This gives you a basic solution which pretty rock-solid, and which you can then fine-tune to the specific requirements of this site.

[DennisCThornton]

Arimo,

Thanks for the feedback.  Yes, the vendor is the one that installed the wireless.  I get the impression that what has happened is that their engineering group designed a install plan and then the "technical" group implements it.  If there is a problem the responsibility stays with the technical group and they don't really know enough to fix a problem install.

My understanding is that the wired network is working fine.  We have had an occasional speed complaint  so we did go ahead and bump the global bandwidth from 8MB to 10MB last week. 

The issues are almost all wireless.  Guest complain that their connection keeps dropping or they cannot connect at all.  Since I'm rarely on site I'm getting this info from the front desk.  So I'm getting a non-computer person's interpretation of a typically non-computer person's ideas on what they think may be happening .... well, you know how usable that info is....

We've tried to see if we could determine if the problems are in certain areas and they are to a slight extent.  There are a couple weak areas.  I've done a couple surveys using vsiwave and that has identified these locations.  We plan on having antennas moved/added to address these spots.  These locations account for only about 10% of the complaints.

The biggest obstacle for me is that I don't have access to the guest services network, only the vendor does.  The guest services network shares the ISP's router with the internal office network, so I can tell if the DS3 connection goes down, which it never has.

Your post gives me a lot of questions I can ask as well as some knowledge to better understand what they're talking about/proposing.

I'll post back once I've had time to review the Implementation guide and get some answers from them.

[Stephen Swain]

I find with MSM765zl and MSM422s the radio selection on AP boot is sub-optimal. Check the site survey for recommended channel pattern, and try setting all of the APs manually to their assigned channels. (In a recent wireless review, I found some areas with multiple APs mostly on the same channel, and some channels unused. I guess it is a function of the timing of the AP boot, if all APs are listening at the same time then the function won't be optimal.

then what else are they going to make channel selection

The radio transmit strength may also not match what the clients are capable of. If the transmit is full power, and the client can't transmit reliably to that AP, then you'll get dropouts. Check the client radio transmit/receive rates, see if some clients only trabsmit back to AP at lowest rates - in the GUI this shows up in the receive graphs.

Sometimes with wireless you can't avoid having to visit and troubleshoot the client onsite, since there may be more involved than just the wireless infrastructure.

Can I recommend a really good tool - Metageek InSSIDer and WiSpy. Two very useful tools.

Regards,

Steve.

[quadt]

I've also had issues with very poor coverage from a stand alone MSM422.  And connections drops occur frequently.  Another thing I find most disturbing is the number of FCS errors that accumulate on the AP even when no users are connected.  They don't start accumulating until about 5 mins after reboot.

I've been working with HP since May on this issue as well as a bunch of issues on my MSM302 AP, which just spontaneously reboot and/or the GUI becomes unresponsive.

I'll post back here if I find anything out.  FYI.. so far the "fix" has been to upgrade the firmware, but it never fixes anything.  My guess is that there is a hardware issue with these units.  It's almost like they are causing themselves interference.

[ISoliman]

Which firmware version you are using ??

[scifan3]

You can capture wireshark packet captures from the AP's... which can help identify what's going on...

You could use something like WIFI inspector (xirrus.com) to perform a quick check of what you can see from a given location...

What firmware version are you running? 

[MFrancisco]

I have the exact same problem. Can someone help?

Apple devices work fine, pc or android have trouble to connect or cant connect at all.

But even with a MacbookPro right under the AP i get lots of destination unreacheable...

CLI# show system info
                                                [CPU info]               [Mem info]
Firmware Version: 5.7.0.2-01-10750         Load 1min:       0.27   Total RAM: 2118230016
Uptime:           57 days, 21:53:>         Load 5min:       0.23    Free RAM: 1884749824
Board Revision:   B:48                     Load 15min:      0.15  Buffer RAM:   17514496
Serial Number:    SG3383N1PT               CPU use now:       3%   Cache RAM:  100438016
                                           CPU 5sec ago:      6%       [Storage use]
                                           CPU 10sec ago:     6%   Permanent:        2%
                                           CPU 20sec ago:     1%   Temporary:        9%

[DennisCThornton]

It's been a while but I thought I'd post back.  We ended up dropping the entire HP wireless setup, but this was not a reflection on HP, but the vendor that installed it (Ibahn).  They used too few APs, didn't set them up properly, and support was substandard at best.   We should have been giving significantly more bandwidth but with the vendor telling us it isn't needed, well ....

I actually got a call from the front desk - they were on the line with support.  The guests could not connect wirelessly and support was saying our internet connection was down.   During this entire time I was VPN'd in doing maintenance on the office portion of the network (yes, over the same internet connection Ibahn support claimed was down).  When a vendor's support group cannot use a simple tool as ping you know it's time to go elsewhere.

We went from 18 APs to a little over 30.  Wireless issues are a thing of the past. 

Sadly the HP equipment is no longer being used and is sitting in a box (reasonably priced if someone is interested).

[MFrancisco]

That's unbeliavable! Even D-Link has better suport then that and you can buy a switch from them for 15€.

I Cant believe i'm going to replace an entire building of HP network devices...