08-11-2012 02:45 PM
So, I spent some time this weekend troubleshooting the issues I've had with the new SG300-28P switch and POE to many of my devices in the office. As a recap, I cannot utilize all of the 24 POE ports on the switch for POE purposes. Really only every other port [with a few odd combinations thrown in between]. In addition, the SG300-28P switch, on occasion, is sending POE to non-POE devices [e.g. my Ruckus Zone Director 1106].
Here are my POE devices [all 802.3 af-compliant]:
I called Cisco support several times in regards to this problem, and they figured it was a hardware issue - a faulty switch. So, Cisco sent me a replacement SG300-28P, which I hooked up today. The exact problem still occurs. Default configuration [fresh out of the box]. No way I can land, for example, the 3 Ruckus 7982 AP's on ports 1, 2, and 3 [or ports 1,13, and 2]. I have to put them on ports 1, 3, and 5 in order for them to power up. In addition, I can't plug any other POE devices on the ports either between or below them. I had to skip another port bay. This is very odd behavior!! Two Cisco SG300-28P's in a row with the same problem.
However, I also had one of the new Cisco SG300-10P switches in my possession for a recent project of ours. I decided to hook up the same POE devices to this switch. ALL POE devices were recognized and worked! No need to skip a port. And it didn't matter what device was plugged in first or not. I am now convinced that it is either a hardware issue [bad power supply/transformer?] inside all of the SG300-28P switches, or a firmware issue.
Both of the SG300-28P switches were running firmware 1.1.2 [the latest on Cisco's website]. So, I decided to install an older firmware version on the SG300-28P switch that I'm returning [installed 1.1.1.8]. Here's what I found out. I could then plug 2 POE devices [e.g. two Ruckus AP's] in adjacent horizontal ports, but not three in a row. In addition, not all adjacent ports. It's funky. For example, I could plug an access point in ports 20 and 21, but not in 21 and 22. No rhyme or reason in how it worked. And I still couldn't plug an access point in adjacent vertical ports [e.g. ports 1 and 13]. BUT...
It's interesting that the same exact switch that would not initially allow 2 horizontally-adjacent POE ports to be utilized WOULD allow 2 horizontally-adjacent POE ports to be utilized when running a different firmware version. It's also interesting to note that when plugged into a "non-working" POE port, the SG300-28P would actually make a small whining noise. Very subtle noise; I could hear it when approx. 1ft away from the switch. The noise was not noticeable when ports were skipped [and POE actually worked]. Therefore, I believe that Cisco has some SG300-28P firmware bugs [at least in the last two versions of firmware] that is not truly allowing all 24 ports to utilize POE correctly. This problem does not exist with the SG300-10P switch.
I'm really interested to hear what Cisco's reply and findings on this matter would be. And would welcome a reply from one of their senior support team members/managers who could actually experiment with this, too. In addition, I'd like to know when they think a solution could be created if it's firmware-related. If hardware-related, I don't think I'll be recommending any 28P switches in our projects. Perhaps just the regular SG300-28 with a separate SG300-10P. It's a shame because the SG300-28P is more of a bargain when compared to the two separate components.
08-11-2012 03:50 PM
Hi John,
Thanks for the interesting post. Can you post a few output commands?
show power inline
show interfaces advertise gigabitethernet xx (for what ports are of interest)
show power inline gigabitethernet xx (for each device plugged in)
show spanning-tree active
A few also things to try and test about to see if there is a way to narrow the process;
After fiddeling with those few settings, see if you can power your products in adjacent ports, etc. Make notes of what works, what doesn't work (if anything at all!)
-Tom
08-11-2012 06:30 PM
Thomas:
Forgive me. My networking skills are not the greatest. [If it weren't for the GUI of the SG300's, I probably would be completely lost.] How do i find these output commands you'd like me to post?
I did try several of the other recommendations you posted in the past. Tried them again, but didn't seem to change anything. I attempted turning off POE off all unused ports. Problem remained - no adjacent port placements of the POE devices. I also turned off CDP on a port-basis inside the SG300-28P. And I set the power inline priority to critical for all POE devices. No such luck. Next, I disabled the EEE globally and per port. No change in actions.
I'm not sure how to check for port flapping [don't know what that is]; however, I can confirm that BPDU guard is disabled/off.
What's really strange is that the default settings of the SG300-10P work just fine, while the default settings of the SG300-28P do not.
Any help with the output commands would be much appreciated.
08-11-2012 06:44 PM
Hi John, enable telnet under security -> TCP / udp services then telnet the switch. Then you may run those commands.
-Tom
04-22-2013 11:21 AM
I have a simular issue with a 802.3af compliant POE Adaptor ( http://www.ubnt.com/8023af )
Invalid Signature Counter rises in the properties section but I never get a POE device to power on at all.
I have updated to the latest software, 1.3 but still no luck.
05-20-2019 09:17 PM
Hi,
i have the same problem here. Is there any the permanent solution for this issue?
thanks.
08-12-2012 12:21 AM
It's definitely not just a straight firmware problem; I've run every version of firmware since 1.0.0.27 on my 28P's and my phones and access points have always worked, power on all 24 ports. The output of those commands Thomas asked for should reveal the usage and class of those PoE devices, among other useful details. I'm curious about this one.
08-13-2012 05:39 AM
show power inline
Port based power-limit mode
Unit Power Nominal Power Consumed Power Usage Threshold Traps
---- ------- ------------- ------------------ --------------- ---------
1 On 180 Watts 13 Watts (7%) 95 Disable
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi1 Auto On critical class0
gi2 Never Off low class0
gi3 Auto Searching critical class0
gi4 Never Off low class0
gi5 Auto On critical class0
gi6 Never Off low class0
gi7 Auto On critical class2
gi8 Auto Searching low class0
gi9 Auto Searching low class0
gi10 Auto Searching low class0
gi11 Auto Searching low class0
gi12 Never Off low class0
gi13 Never Off low class0
gi14 Never Off low class0
gi15 Never Off low class0
gi16 Never Off low class0
gi17 Never Off low class0
gi18 Never Off low class0
gi19 Never Off low class0
gi20 Auto Searching low class0
gi21 Never Off low class0
gi22 Auto Searching low class0
[0mMore:
gi24 Auto Searching low class0
show power inline gigabitethernet xx (for each device plugged in)
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi1 Auto On critical class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is on - valid resistor detected
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 3
Invalid Signature Counter: 17583
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi2 Never Off low class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is off - user setting
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 0
Invalid Signature Counter: 0
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi3 Auto Searching critical class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is off - detection is in process
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 2
Invalid Signature Counter: 1
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi4 Never Off low class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is off - user setting
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 0
Invalid Signature Counter: 0
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi5 Auto On critical class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is on - valid resistor detected
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 0
Invalid Signature Counter: 0
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi7 Auto On critical class2
Power limit (for port power-limit mode): 15.400W
Port Status: Port is on - valid resistor detected
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 0
Invalid Signature Counter: 0
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi13 Never Off low class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is off - user setting
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 1
Invalid Signature Counter: 0
Port Powered Device State Status Priority Class
-------- -------------------- ---------------- ------------ -------- ---------
gi14 Never Off low class0
Power limit (for port power-limit mode): 15.400W
Port Status: Port is off - user setting
Overload Counter: 0
Short Counter: 0
Denied Counter: 0
Absent Counter: 0
Invalid Signature Counter: 0
show interfaces advertise gigabitethernet xx (for what ports are of interest)
Port: gi9
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
Port: gi10
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
Port: gi11
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
Port: gi21
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
Port: gi22
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
Port: gi23
Type: 1G-Copper
Link state: Down
Auto negotiation: Enabled
1000f 1000h 100f 100h 10f 10h
----- ----- ---- ---- --- ---
Admin Local link Advertisement yes no yes yes yes yes
Oper Local link Advertisement - - - - - -
Oper Remote link Advertisement - - - - - -
Priority Resolution - - - - - -
08-13-2012 05:56 AM
I have 6 VLANS configured on our office network. Ideally, I'd like to arrange them in easy clusters [e.g VLAN1 on ports 1,2,3, 13, 14, and 15, etc.] However, I could not get my Ruckus Wireless access points to all come up when doing such. Only by staggering the inputs. Therefore, you'll notice the staggered layout [e.g port 1, 3, and 5] for any device requiring POE.
Ports 9 [vlan4], 10 [vlan1], 11 [vlan1], 22 [vlan1], and 23 [vlan1] are all currently set up to support POE. However, I could not get 3 access points to power up when plugged into any combination of 3 of those ports. Only 2 max.
Port 1 currently has an active access point plugged into it. The other 2 are currently disconnected [although sitting on our lab table as we continue to test these things out]. Again, what's interesting is that if we take the very same POE devices and plug them into the SG300-10P that was temporarily loaded into our equipment rack, we don't have to worry about skipping any ports. All 3 access points can power up just fine [e.g ports 1,2,and 3]. In fact, our entire inventory of POE devices can be plugged into the SG300-10P simultaneously without any problems. Same test gear, different switch. And all those tests were run with the switches in default factory mode and after loading it with a config file. We got the same behavior in either case.
And having both SG300-28P's loaded in our equipment rack, as well, made it real easy to test them with different firmware versions. Both were factory-defaulted. One with 1.1.2. The other with 1.1.1.8. We could easily move the patch cables around as needed. And definitely got a different behavior of how the two handled some of our POE devices.
I found another thread listed here in the Cisco support community: here. Could they be related? However, the Ruckus Wireless 7982 access points are definitely not pre-standard POE devices, as suggested in this other thread. I couldn't quite tell from this thread if there could be an issue, in general, with how power is supplied to 4-port clusters within the 28-port switch. Maybe, I misread the thread. Anyhows, looking forward to your thoughts.
08-13-2012 09:27 AM
Hi John, email or pm me your tele number. I'd like to give you a call around 4pm EST today.
-Tom
10-31-2012 06:48 AM
Hi, was this problem ever resolved? I have the exact same issue with a new SG300-28P using firmware version 1.2.7.76.
Thanks.
10-31-2012 08:01 AM
Hello Harry, can you provide some details?
-Tom
Please rate helpful posts
10-31-2012 08:44 AM
Hi Tom,
I am experiencing very similar issues to what John reported, I am using 8 x Ruckus 7982 access points.
Using factory settings and only applying a management IP address to VLAN1, I find that when plugging each access point in some ports will come on and some simply won't. At first it appeared to be every other port, similar to what John was stating but I have found by playing around that this is not always the case and is very random.
Currently I have access points plugged in and working on ports 1, 2, 4, 5, 7, 9, 11 and 12. If I try to move an access point to a free port none of them work. If I remove all the cables and plug one access point in at a time then some of the ports that were working stop working and I have to plug into each port until one works.
I have checked the power consumption and that is showing 33W with 147W available.
As I only require the 8 access points to be POE and they are all working this is not a huge problem in this scenario but if I wanted to add more it would be. Interestingly if I pull the power out and allow the switch to reboot all the ports that were working continue to work.
Any help or suggestions will be appreciated.
10-31-2012 08:55 AM
Harry, if you'd like, I can give you a phone call today in the later evening, would around 8pm EST be okay?. I'd like to have a session with you to collect data.
-Tom
Please rate helpful posts
10-31-2012 09:23 AM
Sorry Tom I am from the UK and four hours in front of you. I am available any day during the week 8am - 1pm your time. Don't know if this helps, let me know the best way to get my contact details to you.
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