Gig etherchannel between 3508XL and 4507R

Anyone out there doing this? I can get the channel to come up, but the 3508 can only seem to pass traffic on whichever link of the two in the channel comes up first. The 2nd link shows no STP running as I expect it should (based on doing this between a 3550-12G and the 4507R). The result is that I lose connectivity to half the devices attached to the 3508XL (the ones whose traffic is trying to traverse the 2nd link, I would guess).
Cisco TAC hasn't been able to help.
Mike

Hi Mike,
That does sound like a STP problem.
Does 'show spanning-tree blocked ports' show that any of the channel ports are blocking (at either end) ?
And 'show etherchannel port-channel' shows 2 ports in the bundle and both up ?
Thats the kind of thing i would expect to see if the channel was not operating correctly, in which case STP would block one port.
Cheers
Shaun

Similar Messages

  • Gigabit EtherChannel between 6509 and Intel Pro/1000 MTx

    I am trying to configure gigabit etherchannel to connect our backup server with a 6509. The Intel Pro/1000 MT nic in the server has two gigabit ports and supports teaming using LACP. I have configured two gig ports on the 6509 as layer 2 etherchannel ports ( channel-group 2 mode active ). The switch ports always show up as disabled. I can't seem find any documentaion on connecting server to switch using etherchannel ( although the Intel Pro MT nic documentaion does mention it ). Does anyone have experience doing this ?

    We always just use load balancing on the Intel NICs and do nothing with the switch but make sure that the ports are in the correct vlan.
    We have been using this for over 3 years flawlessly.
    Our switches are a Cat4006 and Cat4506.

  • 10G etherchannel between 4510 and 3850 - NO Link

    I'm pulling my hair out on a simple issue, and I could use some advice.   Thank you, in advance.
    I've got a core 4510 switch with 2 12-port 10GE SFP+ modules and my closet has a stack of 3 3850-48p with 2 4-port C3850-NM-2-10G  modules.
    I'm using 4 SFP-10Gb-SR SFP's to create an ether-channel between these two switches.  
    The fiber between them is OM4 cable, and OM3 patch cables.
    The distance is about 90 Meters.
    I've got po8 created on the 4510 through te1/8 and te2/8.  On the 3850, i've got po8 created on te1/1/4 and te3/1/4.  My problem is that I cannot get a link light at all between these ports.  Absolutely nothing indicating when i hook it up.  I've tested all the patch cables using loop backs and they all respond.  I can even loop back through the complete length of the fiber and i get a link light then also. When i hook them up together, the log on the 4510 starts throwing Rx power low alarms with an Operating value of -29.5 dBm.
    I've had Cisco's support go through and verify my port-channel configuration, and they found it to be correct.  
    I'm starting to wonder if there is larger forces at work here.  Am i bumping into a compatibility issue?
    Any help would be appreciated.

    I've removed the interfaces from the etherchannel and tried cross looping.  On the 4510 I get no indication from the LEDs.  On the 3850 I get immediate indication on the LEDs.
    One might conclude, Cisco support included, that the SFPs on the 4510 side were bad and should be replaced.   I hesitate to conclude this because, while members of the etherchannel, i get link lights when looping immediately.  Its only when setting the 4510 interfaces back to default and outside the etherchannel that i don't get a response.

  • Etherchannel between 2900 and 7200

    Hello,
    We have Etherchannel trunk set up between Catalyst 2924 switch and 7200 router. The trunk consists of 2 links with source-based forwarding, STP disabled on switch and on the router. For some reason, we can't achieve load-balancing on the trunk, that is, one link is currently used at 100%, another at 20%. We would like to achieve 50/50 utilization. Is it possible to do?
    Thanks !
    Konstantine

    The Etherchannel trunk consists of 0/11 and 0/12 interfaces.Here's the output from "Show interface" command on a switch:
    FastEthernet0/11 is up, line protocol is up
    Hardware is Fast Ethernet, address is 0001.96bb.51cb (bia 0001.96bb.51cb)
    MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
    reliability 255/255, txload 219/255, rxload 49/255
    Encapsulation ARPA, loopback not set
    Keepalive not set
    Full-duplex, 100Mb/s, 100BaseTX/FX
    ARP type: ARPA, ARP Timeout 04:00:00
    Last input 2w6d, output 00:00:40, output hang never
    Last clearing of "show interface" counters 5w0d
    Queueing strategy: fifo
    Output queue 0/40, 0 drops; input queue 0/75, 0 drops
    5 minute input rate 19376000 bits/sec, 7347 packets/sec
    5 minute output rate 86004000 bits/sec, 8 packets/sec
    FastEthernet0/12 is up, line protocol is up
    Hardware is Fast Ethernet, address is 0001.96bb.51cc (bia 0001.96bb.51cc)
    MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
    reliability 255/255, txload 22/255, rxload 58/255
    Encapsulation ARPA, loopback not set
    Keepalive not set
    Full-duplex, 100Mb/s, 100BaseTX/FX
    ARP type: ARPA, ARP Timeout 04:00:00
    Last input 00:00:08, output 00:00:01, output hang never
    Last clearing of "show interface" counters 5w0d
    Queueing strategy: fifo
    Output queue 0/40, 0 drops; input queue 0/75, 0 drops
    5 minute input rate 22747000 bits/sec, 7947 packets/sec
    5 minute output rate 8678000 bits/sec, 2548 packets/sec
    As you can see, the output rate on interface 0/11 is 300 times lower than on 0/12 and that is our main problem. We have a web farm here (around 100 servers), which is connected via Layer 4 switch to 2924 and then, via Etherchannel trunk, to 7200 router which is default gateway. We tried to use destination-based forwarding (on a switch), but that didn't change anything. The router AFAIK doesn't have any settings to change the forwarding.

  • Etherchannel between wism and C6509

    Hi, when we adding vlans on wism 
    Thats vlans do not appear in configuration on etherchannel and interfaces.
    cisco WS-C6509-V-E Cisco IOS Software, s72033_rp Software (s72033_rp-ADVENTERPRISEK9_WAN-M), Version 12.2(33)SXJ6, RELEASE SOFTWARE (fc3)
    WS-SVC-WISM2-K9  7.6.130.0

    im find, it's bug https://tools.cisco.com/bugsearch/bug/CSCuj96561

  • Trunking between 7613 and GSR (12416)

    Can these 2 devices support gig etherchannelling? I need to trunk 3 gig ethernet between 7613 and 12416. GSR does support portchannels but to allow trunking dot1q must be configured. If any one is doing this please print a sample config.
    Thanks.

    According to the Q&A as below. The Fast and Gigabit Etherchannel is not supported in GSR12000. And it do support 802.1q.
    http://www.cisco.com/en/US/products/hw/routers/ps167/products_qanda_item09186a0080094a71.shtml#n17
    Below is the config, sample for dot1q for VLAN 10 :
    interface gigabitethernet 3/1.1
    encapsulation dot1q 10
    ip address 172.1.1.1 255.255.255.0
    http://www.cisco.com/en/US/products/sw/iosswrel/ps1829/products_feature_guide09186a00800e9556.html#31333
    Hope this helps.

  • EtherChannel between 6006 (catos) and Catalyst 2960 HELP

    Hi All,
    I want to create an etherchannel between 6006 (catos) and Catalyst 2960 to have failover and load balace.
    My ports on 6006 (catos) 6/37,6/47 and on 2960 giga 0/1 and giga 0/2.
    I have checked on 6006 it supports channel.
    Please help to configure this.
    Thanks,
    AS

    AS
    Use this doc as a guide and if you have further questions please come back -
    http://www.cisco.com/en/US/tech/tk389/tk213/technologies_configuration_example09186a0080094953.shtml#specialconsid
    Jon

  • Fast EtherChannel between Catalyst 3750 and 2821 Router

    Hi Guys
    I'm trying to setup a Fast EtherChannel between a cat3750-smi and a 2821 router that consists of only 2 links.
    I am following instructions per TAC, but I'm getting an error along the way;
    On the cat3750:
    interface port-channel 1
    no switchport
    Command Rejected: Not a convertable port
    Can anyone help???
    Also... do the IP Addresses for the EtherChannel need to be the same for both port-channels? Or do I assign the switch like 192.168.1.1 and the router 192.168.1.2 ?
    Thanks!
    Adam

    Hi Adam,
    The ip address cannot be same but it should belong to same subnet. So one side 192.168.1.1 and other side 192.168.1.2 will work fine.
    Its better to convert your layer 2 port as a layer port fist so what you do the port which you want to be port channel go that that interface and convert with "switchport" command
    once it is a layer 3 port configure with channel group and automatically layer 3 port channel will be created and you can sssign an ip address then.
    Just give a try and update if it works.
    Regards,
    Ankur

  • Etherchannel between 2960 switches

    Hello All,
    I configured etherchannel between two 2960 switches.
    Both the switches have SVI with subnet 192.168.2.3 and 192.168.2.4
    I have another vlan3 on one of the switch.
    so when i created etherchannel between two Gig ports and allowed both the vlans,it gave me an error messg,
    Nov  3 12:41:07.332 KSA: %EC-5-CANNOT_BUNDLE2: Gi1/0/19 is not compatible with Gi1/0/20 and will be suspended (vlan mask is different)
    Nov  3 12:41:07.339 KSA: %EC-5-CANNOT_BUNDLE2: Gi1/0/19 is not compatible with Po1 and will be suspended (vlan mask is different)
    Nov  3 12:41:07.339 KSA: %EC-5-CANNOT_BUNDLE2: Gi1/0/19 is not compatible with Po1 and will be suspended (vlan mask is different)
    Nov  3 12:41:07.339 KSA: %EC-5-CANNOT_BUNDLE2: Gi1/0/20 is not compatible with Po1 and will be suspended (vlan m
    May i know why....
    Thanks

    Hello Mudasir
    This will be a problem of allowed vlan mismatch. All the interfaces which are going to add in the etherchannel must have same allowed vlan on both sides.
    You can check for the allowed vlan on all the interfaces as well as on Port-channel.
    You can see the below forum having the same problem:
    https://supportforums.cisco.com/discussion/9757346/etherchannel-prob
    Regards,
    Mukesh Kumar
    Network Engineer
    Spooster IT Services

  • HT1178 What the difference is between WPA and WPA2 and how are these settings affecting the access of other computers to the internet through my Time Capsule

    I have a Time Capsule of the 4th generation and I am pretty impressed since I just had a fried harddrive on my 3 month old Imac and Time Capsule restored it fully including all programs etc. without having me to put in all serial numbers etc. for that I give it an A+. However what I find very frustrating is the very short and incomplete user manual and setup instructions. I give those a D-. It does not explain the consequences of certain choices to a normel non computer gig user like me:
    I do not understand what the consequences and difference is between the security setting WPA/WPA2 and WPA2 when setting it up. It would be helpful if the manual would explain something like: If you set it onto WPA2 then computers older than XXX years will not able to hook up to the internet through your router...or the likes, since I slowly supect this may be the reason for some of my troubles.
    I also have a 5 year old PC with vista connected to the Time Capsule. It can wireless connect to the Time Capsule and access the printer (I have managed that after some painful hours...) but it cannot access the internet with that PC through the timecapsule wireless, only if I hook it up with a cable. Why? Does that have to do with the fact that I have set the TIme Capsule to WPA2?
    Our PS3 can connect wireless, no problem. However, I friend of mine tried it with a quite new Toshiba Notebook and he could see the Time Capsule but again it shows the line from the Time Capsule to the internet blocked. All other computers linked with data cable to the Time Capsule are connected to the internet no problem. What have we done wrong? Should I change the security setting to WPA/WPA2?
    I tried the latter, but then another problem does come up, which was there from beginning on: When I change the settings for my Time Capsule my Imac suddenly cannot find the Timne Capsule anymore, even so I am only 3feet away from it. When I set it up for the first time 3 month ago it drove me crazy. The very first time it found the Time Capsule right away. But when I discuverd a mistake in my initial setup and I went through the settings again to change stuff it suddenly could not find the Time Capsule anymore. Only after frustrating 20 times or so with turning wi-fi on and off several times inbetween did it suddenly find the Time Capsule in the set up menu. However, when I tried changing my security setting to WPA/WPA2 today to see whether this solves my other problems again it could not find the Time Capsule when I was finished with the settings and I had to give up/cancel. Why is that???
    I would really appreciate some help here. But please I am not a computer gig and normally always had assistance with these things. On the other hand I am not all stupid either (even so these manuals assuming we all grew up sleeping on a computer make me feel stupid).....
    Thank you all in advance

    Hello Schimi. The Time Capsule is a kind of product that offer you two possibility:
    - To use the TC as a router or as an external HD.
    The difference between WPA and WPA 2 are:
    - They are two kinds of internet connection.
    WPA uses dynamic key encryption , which means that the key is constantly changing and makes the invasion of a wireless network more difficult than WEP . WPA is considered one of the highest levels of wireless security for your network and is recommended if your devices support this kind of encryption . Newer routers offer WPA2 security . WPA2 is compatible with WPA , but offers higher security level . In fact, it meets the high standards of many government agencies . If the router and computer support WPA2 , this should be your choice.
    If you need any help or if you find some difficult setting up it you can contact Apple Support.
    I am sure that they can help you with that.
    I am sory for the delay. I holpe that you solve your issue.

  • Differences between mcp and mcp t sound

    this is all sound sound info direct from a man at nvidia who knows
    PLEASE NOTE ONLY MCP2-T BOARD MSI DO AT THE MOMMENT IS THE K7N2G-ILSR
    The MCP has no hardware support for audio of any kind, period. Windows and the CPU do all the audio work on that part and there is absolutely no DSP, NVIDIA or otherwise, in that chip to help out. Try to do EAX, any kind of reverb or chorus, or a music preset on those boards and you'll see the CPU usage climb. Ditto if you add more voices to the mix: CPU usage goes up.
    The MCP-T has a full hardware audio DSP, hardware acceleration for 2D and 3D streams, and Dolby Digital encode support. EQs, HRTFs, and all environmental settings are exposed and modifiable by the user. None of this is available on the soft solutions due to the heavy hit on the CPU if they were enabled.
    Short of that, you can try to use the ASIO or OpenAL drivers. You'll find that neither will work on the MCP because there is no supporting hardware for them. In short, there is no way to coax an MCP to be an APU capable part, the support simply isn't in the chip
    Here's the chip differences:
    MCP has the following:
    - ATA-133 x 2 ports
    - USB 1.0/1.1/2.0 x 6 ports
    - NVIDIA MAC 10/100 x 1 port
    - Legacy I/O bus (PS2, Printer, Serial)
    - AC 97 host based audio (no DSP)
    MCP-T includes the above and adds the following:
    - 3Com MAC 10/100 x 1 port
    - 1394A Firewire MAC x 3 ports
    - NVIDIA APU with Dolby Digtal Encoder

    thats not to say mcp is bad as this proves
    The MCP2 is definately hardware sound. As far as the APU goes the only difference between MCP2 and MCP2-T is the T version has Soundstorm(Dolby Digital). Basically Mcp2-T =5.1 digital output capabilities Mcp2 no digital output, analogue output only. The other differences are the T version Has Dual Lan support and a firewire controller which the plain MCP2 does not. Here are my cpu utilization test results from Audio winbench proving that The MCP2 APU is a hardware APU.
    http://www.nforcershq.com/forum/viewtopic.php?p=28870#28870
    to see the test he ran ,will not copy /paste
    MSI K7N2-L Mainboard
    Athlon XP 2000+ Retail cooler
    MSI Geforce3 TI 200
    1Gig (2x512) Kingston pc2700 Ram
    Maxtor DiamondMax Plus 9 8meg cache 80 gig
    WD 600BB 60 gig
    Onboard Nforce 2 APU (no soundstorm
    just to explain differences

  • 10Gig (tengigabit) CRC Errors between N5K500 and 3750X

    Dear Forum,
    We have an issue with a 10 Gig connection between a Nexus 5548 and a 3750X 10Gig. There is also a HSRP group running over this link with aggressive timeouts which recently behaves somewhat unstable. We noticed a bunch of CRC errors on this link on the 3750X side (about 300 per hour) and assume that these are related to the HSRP troubles once or twice a day.
    Originally the connection was made with a twinax cable. We already changed to MMF fiber with SR SFP+'s. The 10Gig Uplink Module in the 3750x has been replaced already. All to no avail. Now it's up to replace the 3750 (receives CRC) or the Nexus Chassis (sending device)
    I was wondering if there is some experience on the list what is the most probably cause and solution here.
    Thanks in advance,
    Michael.

    MTU is 1500 bytes, on both sides (I think) see output below. Strangely enough the NX has a non-zero Jumboframe counter (increasing).
    C3750#sh int te3/1/1
    TenGigabitEthernet3/1/1 is up, line protocol is up (connected)
      Hardware is Ten Gigabit Ethernet, address is 4055.3992.111d (bia 4055.3992.111d)
      Description: TO_100C_PO913
      MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
         reliability 255/255, txload 2/255, rxload 1/255
      Encapsulation ARPA, loopback not set
      Keepalive not set
      Full-duplex, 10Gb/s, link type is auto, media type is SFP-10GBase-SR
      Media-type configured as  connector
      input flow-control is off, output flow-control is unsupported
      ARP type: ARPA, ARP Timeout 04:00:00
      Last input 00:00:55, output 00:00:41, output hang never
      Last clearing of "show interface" counters 04:10:35
      Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
      Queueing strategy: fifo
      Output queue: 0/40 (size/max)
      5 minute input rate 4011000 bits/sec, 1091 packets/sec
      5 minute output rate 110431000 bits/sec, 16489 packets/sec
         37040147 packets input, 35868731879 bytes, 0 no buffer
         Received 1071851 broadcasts (935322 multicasts)
         0 runts, 0 giants, 0 throttles
         1002 input errors, 1002 CRC, 0 frame, 0 overrun, 0 ignored
         0 watchdog, 935322 multicast, 0 pause input
         0 input packets with dribble condition detected
         182446795 packets output, 69097435882 bytes, 0 underruns
         0 output errors, 0 collisions, 0 interface resets
         0 babbles, 0 late collision, 0 deferred
         0 lost carrier, 0 no carrier, 0 PAUSE output
         0 output buffer failures, 0 output buffers swapped out
    C3750#sh int te4/1/1
    TenGigabitEthernet4/1/1 is up, line protocol is up (connected)
      Hardware is Ten Gigabit Ethernet, address is 4055.39bd.001d (bia 4055.39bd.001d)
      Description: TO_100D_PO913
      MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
         reliability 255/255, txload 1/255, rxload 1/255
      Encapsulation ARPA, loopback not set
      Keepalive not set
      Full-duplex, 10Gb/s, link type is auto, media type is SFP-10GBase-SR
      Media-type configured as  connector
      input flow-control is off, output flow-control is unsupported
      ARP type: ARPA, ARP Timeout 04:00:00
      Last input 00:00:14, output 00:00:33, output hang never
      Last clearing of "show interface" counters 04:10:38
      Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
      Queueing strategy: fifo
      Output queue: 0/40 (size/max)
      5 minute input rate 161000 bits/sec, 215 packets/sec
      5 minute output rate 29493000 bits/sec, 9580 packets/sec
         3264201 packets input, 318586322 bytes, 0 no buffer
         Received 1130048 broadcasts (1020339 multicasts)
         0 runts, 0 giants, 0 throttles
         501 input errors, 501 CRC, 0 frame, 0 overrun, 0 ignored
         0 watchdog, 1020339 multicast, 0 pause input
         0 input packets with dribble condition detected
         168673910 packets output, 87266013753 bytes, 0 underruns
         0 output errors, 0 collisions, 0 interface resets
         0 babbles, 0 late collision, 0 deferred
         0 lost carrier, 0 no carrier, 0 PAUSE output
         0 output buffer failures, 0 output buffers swapped out
    N5K connected to 3/1/1:
    Ethernet1/1 is up
      Hardware: 1000/10000 Ethernet, address: 0005.9b1f.8648 (bia 0005.9b1f.8648)
      Description: CHANNEL_TO_RO015A
      MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
      reliability 255/255, txload 1/255, rxload 3/255
      Encapsulation ARPA
      Port mode is trunk
      full-duplex, 10 Gb/s, media type is 10G
      Beacon is turned off
      Input flow-control is off, output flow-control is off
      Rate mode is dedicated
      Switchport monitor is off
      EtherType is 0x8100
      Last link flapped 2d04h
      Last clearing of "show interface" counters never
      30 seconds input rate 96695496 bits/sec, 16464 packets/sec
      30 seconds output rate 4715024 bits/sec, 1868 packets/sec
      Load-Interval #2: 5 minute (300 seconds)
        input rate 148.33 Mbps, 20.23 Kpps; output rate 2.90 Mbps, 1.13 Kpps
      RX
        26173471641 unicast packets  6446061938 multicast packets  24295222 broadcas
    t packets
        32643828801 input packets  16853116460189 bytes
        7772805495 jumbo packets  0 storm suppression packets
        0 runts  0 giants  0 CRC  0 no buffer
        0 input error  0 short frame  0 overrun   0 underrun  0 ignored
        0 watchdog  0 bad etype drop  0 bad proto drop  0 if down drop
        0 input with dribble  0 input discard
        0 Rx pause
      TX
        48369101239 unicast packets  462061134 multicast packets  81589744 broadcast
    packets
        48912752123 output packets  56533126796163 bytes
        35421478216 jumbo packets
        6 output errors  0 collision  0 deferred  0 late collision
        0 lost carrier  0 no carrier  0 babble 0 output discard
        0 Tx pause
      3 interface resets
    N5K connected to 4/1/1:
    Ethernet1/1 is up
      Hardware: 1000/10000 Ethernet, address: 0005.9b1f.8188 (bia 0005.9b1f.8188)
      Description: CHANNEL_TO_RO0015A
      MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
      reliability 255/255, txload 1/255, rxload 1/255
      Encapsulation ARPA
      Port mode is trunk
      full-duplex, 10 Gb/s, media type is 10G
      Beacon is turned off
      Input flow-control is off, output flow-control is off
      Rate mode is dedicated
      Switchport monitor is off
      EtherType is 0x8100
      Last link flapped 2d04h
      Last clearing of "show interface" counters never
      30 seconds input rate 20643816 bits/sec, 10541 packets/sec
      30 seconds output rate 142592 bits/sec, 180 packets/sec
      Load-Interval #2: 5 minute (300 seconds)
        input rate 25.50 Mbps, 9.49 Kpps; output rate 159.20 Kbps, 142 pps
      RX
        119855915845 unicast packets  6017690609 multicast packets  20318382 broadca
    st packets
        125893924837 input packets  124351081100162 bytes
        70763564145 jumbo packets  0 storm suppression packets
        0 runts  0 giants  1 CRC  0 no buffer
        1 input error  0 short frame  0 overrun   0 underrun  0 ignored
        0 watchdog  0 bad etype drop  0 bad proto drop  0 if down drop
        0 input with dribble  0 input discard
        0 Rx pause
      TX
        20958491666 unicast packets  503446052 multicast packets  52796318 broadcast
    packets
        21514734036 output packets  29748981423583 bytes
        18964491576 jumbo packets
        0 output errors  0 collision  0 deferred  0 late collision
        0 lost carrier  0 no carrier  0 babble 0 output discard
        0 Tx pause
      3 interface resets

  • Comparison between 3750 and 3750-metro

    hi folks,
    is there any links which will provide me on the comparison between 3750 and 3750-metro? for exapmple, isis is not support on 3750 but it support on 3750-metro. The product information from cisco site is insufficient in term of the main differences :p
    rgd
    josh.w

    Hi Josh,
    The Cisco Catalyst 3750 Metro Series is built for Metro Ethernet access in a customer location, enabling the delivery of more differentiated Metro Ethernet services. These switches feature bidirectional hierarchical QoS and Traffic Shaping, intelligent 802.1Q tunneling with class-of-service (CoS) mutation, VLAN translation, MPLS, EoMPLS, and Hierarchical Virtual Private LAN Service (H-VPLS) support, and redundant AC or DC power. They are ideal for service providers seeking to deliver profitable business services, such as Layer 2, Layer 3, and MPLS VPNs, in a variety of bandwidths and with different SLAs.
    The metro switches have the PXF chips (which allow hierarchical QoS on the 2 "WAN" GigE ports, so several logical links can share a connection, and have soft bandwidth limits).
    For more details on 3750-M switches have a look at this link
    http://www.cisco.com/en/US/products/hw/switches/ps5532/products_qanda_item09186a00801eb822.shtml
    HTH
    Ankur
    *Pls rate all helpfull post

  • Difference between Null and null?

    What is the difference between null and NULL?
    When is each used?
    Thanks,

    veryConfused wrote:
    There is a null in java, but no NULL. null means no value. However, when assigning value, the following is different:Although the empty String has no special role. Null means, the referential type is not assigned (doesn't refer) to a specific object. The empty String is just another object though, so seeing it or pointing it out as something special when it actually isn't at all (no more special than new Integer(0) or new Object[0]) just adds to the confusion.

  • 7344 servo motion switching between open and closed loop operation

    I have a custom end-of-line test system presently using a 4-axis 7344 servo controller to perform various functional tests on small, brushed DC motors. The system is programmed in C/C++ and uses flex motion functions to control the motor during testing. Motors are coupled to external encoder feedback and third party PWM drives running in closed-loop torque mode from an analog command signal. The system uses all four motion axis channels on the 7344 board to independently and asynchronously test up to four production motors at a time.
    In closed-loop mode, the system runs without issue, satisfying the battery of testing protocols executed by this system. I now have a request to add additional test functionality to the system. This testing must be run in open loop mode. Specifically, I need to use my +/- 10v analog output command to my torque drive to send different DAC output levels to the connected motor.drive while monitoring response.
    I do not believe the flex motion library or 7344 controller includes functions to easily switch between open and closed loop mode without sending a new drive configuration. I am also under the impression that I cannot reconfigure one (or more) servo controller axis channels without disabling the entire drive. As my system runs each axis channel in an asynchronous manner, any requirement to shutdown all drives each time I change modes is an unworkable solution.
    I am open to all ideas that will allow asynchronous operation of my 4 motor testing stations. If the only solution is to add a second 7344 controller and mechanical relays to switch the drive and motor wiring between two separately configured servo channels, so be it. I just want to explore any available avenue before I place a price tag on this new system requirement.
    Bob

    Jochen,
    Thank you for the quick response. The 7344 board does an excellent job running my manufacturing motor assemblies through a custom end-of-line tester in closed loop mode. A portion of the performance history and test result couples the motor through a mechanical load and external shaft. The shaft is in contact with a linear encoder that closes my servo loop.
    My new manufacturing requirement is to also sample/document how the small DC motor behaves in open loop operation. Your solution is exactly what I need to perform the additional functional tests on the product I am manufacturing. I see no reason why this cannot work. I was originally concerned that I would need to reinitialize the 7344 board after changing axis configuration. Initialization is a global event and impacts all four channels on the 7344 board.
    Using flex_config_axis() to change axis configuration on a single channel without disturbing other potentially running axis channels will solve my concern. It will be several weeks before I can return to the manufacturing facility where the 7344-based testing machine is located. I will update this thread once I verify a successful result.
    Bob

Maybe you are looking for