2 Switch stack Design for redundancy

Hi Everyone,
I need to connect 2 switches in stack which will connect to 2 servers.
Each server will habe 12 NICs.
So for Redundancy purposes i can connect 6 ports from server A to Switch 1
6 Ports from server A to Switch 2
Same way i can do
6 ports from Server B to Switch 1
6 ports from Server B to switch 2
IF i go with above design and in case say switch 2 dies then stack will have single switch will it cause any outage?
Regards
Mahesh

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
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In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
IF i go with above design and in case say switch 2 dies then stack will have single switch will it cause any outage?
It depends.
One of your two switches will run in the role of switch master, and if that switch fails, there's a brief impact as control plane function are taken over by the second switch. Whether this control plane switch over causes any impact to the server hosts depends on switch configuration and how (via L2 or L3) the hosts are communicating to other hosts. For example, if you're running default, regarding master switch MAC persistence, that MAC will change, which I understand, will drop Etherchannel.

Similar Messages

Design for redundancy of access switch

hello all,
I have the following design for a site:
Provider delivers channel with HSRP redundant routers, but access level in not redundant and represented by one switch.
Am I correct that there is no way no provide redundancy on access level only with access switches or there are any design proposals?!

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
As Reza describes, many hosts only have a single connection to network, so that single connection is always a possible point of failure. But there's a couple of things you can do to minimize the impact of a network infrastructure device failure.
When working with small appliance type switches, you might have multiple smaller switches rather than one large switch. For example, instead of having one 48 port switch, you might have two 24 ports switches, or six 8 port switches, etc.. If a switch fails, not all hosts lose connectivity.
You can also have additional ports, ideally enough to handle lost of any one unit of hardware, So, for example, if you have seven 8 port switches, when you only need 48 ports, if a switch fails, you only lose 1/7 of your hosts until they can be repatched into available ports on the other switches.
If some of your hosts have multiple NICs, then there are various method to use the two NICs to avoid a single network unit failure from dropping the host. Usually only shared servers merit that level of redundancy.

Challenge: Spanning Tree Control Between 2 links from Switch DELL M6220 to 2 links towards 2 switches CISCO 3750 connected with an stack (behavior like one switch for redundancy)

Hello,
I have an Spanning tree problem when i conect 2 links from Switch DELL M6220 (there are blades to virtual machines too) to 2 links towards 2 switches CISCO 3750 connected with an stack (behavior like one switch for redundancy, with one IP of management)
In dell virtual machine is Spanning tree rapid stp, and in 3750 is Spanning tree mode pvst, cisco says that this is not important, only is longer time to create the tree.
I dont know but do you like this solutions i want to try on sunday?:
Could Spanning tree needs to work to send one native vlan to negociate the bdpus? switchport trunk native vlan 250
Is it better to put spanning-tree guard root in both 3750 in the ports to mitigate DELL to be root in Spanning Tree?
Is it better to put spanning- tree port-priority in the ports of Swicht Dell?
¿could you help me to control the root? ¿Do you think its better another solution? thanks!
CONFIG WITH PROBLEM
======================
3750: (the 2 ports are of 2 switches 3750s conected with a stack cable, in a show run you can see this)
interface GigabitEthernet2/0/28
description VIRTUAL SNMP2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 4,13,88,250
switchport mode trunk
switchport nonegotiate
logging event trunk-status
shutdown
interface GigabitEthernet1/0/43
description VIRTUAL SNMP1
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 4,13,88,250
switchport mode trunk
switchport nonegotiate
shutdown
DELL M6220: (its only one swith)
interface Gi3/0/19
switchport mode trunk
switchport trunk allowed vlan 4,13,88,250
exit
interface Gi4/0/19
switchport mode trunk
switchport trunk allowed vlan 4,13,88,250
exit

F.Y.I for catylyst heroes - here is the equivalent config for SG-300 - Vlan1 is required on the allowed list on the catylyst side (3xxx/4xxx/6xxx)
In this example:
VLANS - Voice on 188, data on 57, management on 56.
conf t
hostname XXX-VOICE-SWXX
no passwords complexity enable
username xxxx priv 15 password XXXXX
enable password xxxxxx
ip ssh server
ip telnet server
crypto key generate rsa
macro auto disabled
voice vlan state auto-enabled !(otherwise one switch controls your voice vlan….)
vlan 56,57,188
voice vlan id 188
int vlan 56
ip address 10.230.56.12 255.255.255.0
int vlan1
no ip add dhcp
ip default-gateway 10.230.56.1
interface range GE1 - 2
switchport mode trunk
channel-group 1 mode auto
int range fa1 - 24
switchport mode trunk
switchport trunk allowed vlan add 188
switchport trunk native vlan 57
qos advanced
qos advanced ports-trusted
exit
int Po1
switchport trunk allowed vlan add 56,57,188
switchport trunk native vlan 1
do sh interfaces switchport po1
!CATYLYST SIDE
!Must Explicitly allow VLan1, this is not normal for catalysts - or spanning tree will not work ! Even though it’s the native vlan on both sides.
interface Port-channel1
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,56,57,189
switchport mode trunk

Snmp for 3750 switch stack

Hi,
I have two 3750 switch stack together with one ip address mange the stack.
Can I monitor the memory and cpu for each individual switch? what is the oid then?
Thanks.
C.K.

Hello CK,
On the Catalyst 3750, the stack master handles the SNMP requests and traps for the whole switch stack.
The stack master transparently manages any requests or traps that are related to all stack members. When a new stack master is elected, the new master continues to handle SNMP requests and traps as configured on the previous stack master, assuming that IP connectivity to the SNMP management stations is still in place after the new master has taken control.
So to answer your question, with the OID for CPU and Mempory usage the switch will return only values for the active master. The other stack members are hot standby and do not produce SNMP information for CPU and/or Memory.
HTH
--Leon

Removing 4 out of 6 switches in a switch stack

Hi all,
A very simple question for the group (I hope!) regarding 3750 switch stacks.
I've inherited a stack of 6 3750 switches. I need to reduce this to two. All of my active connections have been moved over to the remaining two switches I plan to keep.
Here is the output of the show switch
DASW01_4STACK#sh switch
Switch/Stack Mac Address : 001c.b1d9.cb80
                                           H/W   Current
Switch# Role   Mac Address     Priority Version State
1       Member 0019.2f07.ab80     1      0       Ready
*2       Master 001c.b1d9.cb80     1      0       Ready
3       Member 001c.b1e1.5d80     1      0       Ready
4       Member 001c.b1f6.4a80     1      0       Ready
5       Member 0023.eabd.3500     1      0       Ready
6       Member 001c.0ea1.be80     13     0       Ready
The two switches I want to keep are # 5 and #6.
As you can see, for some reason the master is not on switch 6 even though it has the highest priority. All the switches are connected together with the proper redundant stack cables.
I've never worked with stacks before but would the actions be as simple as.
1. Backup configs!
2. Turn off switches 1 to 4 one at a time an allow for the stack to stabilize after each switch is powered down.
3. Verify that switch 6 is now the master and everything still works.
4. Turn off switch 5 & 6 and connect the stack cables of each switch to each other for redundancy (currently only one cable connects switch 5&6)
5. Turn on switch 5 & 6
Am I missing anything?
Thank you!
-Pete

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Leo Laohoo wrote:"Power off the switch that is to be added."But Joseph you are not ADDING switches. You are REMOVING switches from a stack and re-cabling.If one was adding a new switch, then yes, I recommend the new switch is to be powered OFF before connect the stacking cable.
Leo, an excellent point!
Powering of the switch, when "adding" to the stack, no doubt gets it to initiate itself as a stack member.
Re-cabling existing stacks members, shouldn't need that, but the question then is whether the hardware (stack connections) were designed for making "hot" (i.e. both sides powered on) connections. If they are, then you're correct, no need to power off switch 5.

Metro Ethernet Design With Redundant Head Ends

We're getting ready to turn up some metro ethernet circuits that were just installed by AT&T. AT&T has provided a VLAN for each remote site (so each site has its own VLAN), and those VLANs are trunked to our head end switches (Cisco 3750 Metro Switches).
I'm struggling with the best design for IP routing. We currently use OSPF on our internal network, and I was going to extend OSPF to our metro solution as well, but I'm not so sure now.
I don't want routing to occur directly between head end #1 and head end #2, we already have redundant paths within our corporate network, and allowing our two head ends to route between each other via our metro ethernet solution is not what we want. However, running OSPF on each of the VLANs which have been provisioned for us would permit routing between the head ends.
We simply need to allow redundanny for our remote locations in the event that one head end were to fail, all of the traffic to/from the remote site would be routed through the head end which is still online.
Anyone suggestions on the best routing design for this situation would be greatly appreciated. I've attached a network diagram to make things clear. I believe I can also go back to AT&T and request one VLAN that includes all sites if that would simply things. I just need to make sure I can still do our traffic shaping because the remote sites are only 10mbps and the head ends are 1gbps.
Thanks,
-Steve

just at a glance it looks as if you should be able to have stp on and setup 1 site as primary and other as secondary

Blocked Stack Ports on 2960X-48FPD-L Stack (Unstable Switch Stack!) Spanning Tree?

I am having an issue where 2 2960X-48FPD-L Switches in a redundant flexstack (stack port 1 SW1 to port 2 SW2 and port 2 SW1 to port 1 SW2) ring.
At first running the 15.0(2).EX5 (and earlier EX3, and EX4) version IOS yielded all the ports on the stack master switch refusing to run spanning tree and would only link in amber and not pass any traffic other than CDP information (the slave switch linked in fine).
I upgraded to 15.2(3)E and this solved the problem of the ports not linking in green and participating in spanning tree.
Now, however, about every week or two I lose connectivity to the switch stack and I was able to go to the switch stack locally and found that for some reason the switch stack is blocking and unblocking VLANs on StackPort1 frequently (see below). When I was at the site, I sometimes had connectivity, sometimes not. A stack hard reboot brought everything back up, but this is the second time this has occurred and I would expect the same problem in the next week or so.
Has anyone else run into these issues, and have you found a solution?
I'm guessing that if I either get rid of the redundancy on the switch stack or stack using Ethernet cables between switches the problem will go away, but then what is the point of using stackable switches in a non redundant low speed stack. It seems to me that Spanning tree thinks that I have a spanning tree loop going on with the stack ports which I didn't even think was possible.
What do you think?
Jim
_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:02:59: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking StackPort1 on VLAN0307. Port consistency restored.
Mar 11 09:03:16: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:03:27: %SPANTREE-2-BLOCK_PVID_PEER: Blocking StackPort1 on VLAN0307. Inconsistent peer vlan.
Mar 11 09:03:42: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking StackPort1 on VLAN0307. Port consistency restored.
Mar 11 09:03:46: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:03:47: %SPANTREE-2-BLOCK_PVID_PEER: Blocking StackPort1 on VLAN0307. Inconsistent peer vlan.
Mar 11 09:04:12: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking StackPort1 on VLAN0307. Port consistency restored.
Mar 11 09:04:22: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:04:56: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:05:13: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 207 on StackPort1 VLAN307.
Mar 11 09:05:13: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking StackPort1 on VLAN0307. Inconsistent local vlan.
Mar 11 09:05:30: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:06:00: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:06:04: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking StackPort1 on VLAN0307. Port consistency restored.
Mar 11 09:06:32: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:07:02: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:07:03: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 207 on StackPort1 VLAN307.
Mar 11 09:07:03: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking StackPort1 on VLAN0307. Inconsistent local vlan.
Mar 11 09:07:34: %SPANTREE-2-RECV_BAD_TLV: Received SSTP BPDU with bad TLV on StackPort1 VLAN1.
Mar 11 09:07:45: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking StackPort1 on VLAN0307. Port consistency restored.

Jim,
We have also the same problem with our 2960-X switches (access) connecting to a pair of 4500x (VSS) except our issue is with Portchannel with 2 physical links connecting the 2960xs to the 4500.
If we disconnect one of the physical links from the portchannel everything works fine, but when we connect the same physical link back all users lose connectivity and the physical link starts flapping. Here are some of the messages we see in the logs when both physical links are in the portchannel:
Mar 10 18:00:43 EST: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 1 on Port-channel5 VLAN90.
Mar 10 18:00:43 EST: %SPANTREE-2-BLOCK_PVID_PEER: Blocking Port-channel5 on VLAN0001. Inconsistent peer vlan.
Mar 10 18:00:43 EST: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking Port-channel5 on VLAN0090. Inconsistent local vlan.
Mar 10 18:00:58 EST: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking Port-channel5 on VLAN0001. Port consistency restored.
Mar 10 18:00:58 EST: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking Port-channel5 on VLAN0090. Port consistency restored.
Mar 10 18:01:29 EST: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/0/1, changed state to down
Mar 10 18:01:37 EST: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/0/1, changed state to up
Mar 10 18:01:48 EST: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/0/1, changed state to down
Mar 10 18:01:51 EST: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/0/1, changed state to up
We have upgraded to 15.0(2a).EX5 and still have the same issue.
We have a ticket open with Cisco and have sent them all the logs and debugs and waiting to hear back from IOS developers.
HTH

2960X Switch Stack Master Switch all ports only link in Orange

I have 2 Cisco 2960X-48FPD-L switches running the latest version 15.0(2)EX5 software in a stack using the flex stack modules and 2 stacking cables between them.
The problem I am having is that even though I can manage the entire stack without issues the master switch for some reason will not let me link any devices of SFP's fully in. If I plug any device or fiber link in the show interface shows link and line protocol up but the ports only link in orange. I can see the connected devices via a show CDP neighbor command but cannot connect to them and if I do a show spanning-tree it says I have no spanning tree instances.
The second switch (non master) all ports link in just fine green and I can connect to it from the rest of my network via a fiber link on the SFP port. A show spanning-tree also shows the correct information for the spanning tree instance for the second switch.
Has anyone run into this and if so is there an easy solution?
Jim

Unfortunately removing the "cluster enable Switch-2960X-Cluster 0" configuration did not fix my issue. However I have found the following while troubleshooting that may be useful.
1. The problem seems to exist only on whichever switch is designated the master switch, connections to the member switch work fine.
2. If I switch the priority such that on a reboot the switches swap roles (Master to Member and vice versa) the ports that were linking in green, now link in orange and stop passing traffic and the ports that were linking in orange now link in green and start passing traffic. (Simply, the switch that is master will not link any ports in green only the switch designated as master).
3. Strangely the ports that link in orange show interface and line protocol up and I can see devices such as IP Phones and other switches with a show CDP neighbor and a show CDP neighbor detail. However they can't receive an ip address from the DHCP server and can't pass high level traffic.
4. The switch ports that are linked in only orange do not show up in the output of a "Show Spanning-Tree" command.
What do you think? This is really stumping me.

Design for "featured providers"

I don't know what the feature is called but when you click in the itunes store on podcast and then on "featured providers" then you can see that big podcast providers with more than one podcast seem to have their own "chapter" "section" or whatever it is called. (so what is it called?). Just take a look at BBC for example. It is defined by a distinct design with a huge space on top with their logo and image material and a text block. Further down you have a box with all their podcasts.
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Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
As Reza describes, many hosts only have a single connection to network, so that single connection is always a possible point of failure. But there's a couple of things you can do to minimize the impact of a network infrastructure device failure.
When working with small appliance type switches, you might have multiple smaller switches rather than one large switch. For example, instead of having one 48 port switch, you might have two 24 ports switches, or six 8 port switches, etc.. If a switch fails, not all hosts lose connectivity.
You can also have additional ports, ideally enough to handle lost of any one unit of hardware, So, for example, if you have seven 8 port switches, when you only need 48 ports, if a switch fails, you only lose 1/7 of your hosts until they can be repatched into available ports on the other switches.
If some of your hosts have multiple NICs, then there are various method to use the two NICs to avoid a single network unit failure from dropping the host. Usually only shared servers merit that level of redundancy.

Can I use DHCP snooping and IOS DHCP server on the same switch stack

Hello,
I am shortly going to be deploying a Cisco CallManager solution for a customer whose network comprises stacks of Catalyst 3850 switches.
There is no separate core/server farm switch so the CallManager servers, voice gateways and IP phones will all plug into the same stack and be in the same VLAN (not my choice!).
For security we want to enable DHCP snooping and were planning on using the IOS DHCP server on the Catalyst switch stack.
Will this work? - when I enable DHCP snooping in networks with separate access layer switches I set the uplinks to the core as trusted links.
I am not sure whether DHCP snooping will work in this case. Do I need to set the VLAN interface on the switch as trusted, is this even possible?
Unfortunately I do not have access to a layer 3 switch to test this at the moment.
Thanks

Nope. That's the issue.
They'll sync on a third device acting as a hotspot, but the device sending a signal is not "on" the network it creates so the airport is all by itself on that network. At least that is what it looks like to me. Anyone have another take on it? Seems pretty silly that an iPad can put out a wifi signal, an Airport Express can receive a wifi signal, and yet there is no simple way to get them to communicate under this particular condition.

In Flash Builder: "No Disk" Error when trying to switch to Design View

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When I try to switch to Design View or open a link from Start Page in Flash Builder Beta 2, the application freezes and "No Disk" error message pops up.

You have some other problem with your boot drive that has corrupted data backed up to the TimeMacine drive.
My advice is to boot into each operating system and manually backup just your Users files each to separate regular external drives (no Timemachine or backup software) and disconnect.
Make a note of any serial numbers, emails, address book contacts, export bookmarks etc. that isn't typically in your users folders data.
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Most commonly used backup methods
If your OS X parititon doesn't boot, you can use this to recover files.
Create a data recovery/undelete external boot drive
Without any further detail about your machine I can't advise specifically what to do, but it involves using Disk Utility to Zero Erase (move slider one spot to the right or in 10.6 using Security Option) the ENTIRE boot drive and reformatting, then installing OSX fresh and then setting up BootCamp again.
If you wish to switch your boot drive for something better, this is a good time to do this.
Install/upgrade RAM or storage drive in Mac's
If your machine is capable of Internet Recovery, then use that, then upgrade.
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Stack size for native thread attaching to JVM

All:
I have a native thread (see below, FailoverCallbackThread) that attaches to the JVM and does a Java call through JNI. The stack size for the native thread is 256KB.
at psiUserStackBangNow+112()@0x20000000007a96d0
at psiGuessUserStackBounds+320()@0x20000000007a8940
at psiGuessStackBounds+48()@0x20000000007a8f60
at psiGetPlatformStackInfo+336()@0x20000000007a9110
at psiGetStackInfo+160()@0x20000000007a8b40
at psSetupStackInfo+48()@0x20000000007a5e00
at vmtiAttachToVMThread+208()@0x20000000007c88b0
at tsAttachCurrentThread+896()@0x20000000007ca500
at attachThread+304()@0x2000000000751940
at genericACFConnectionCallback+400(JdbcOdbc.c:4624)@0x104b1bc10
at FailoverCallbackThread+512(vocctx.cpp:688)@0x104b8ddc0
at start_thread+352()@0x20000000001457f0
at __clone2+208()@0x200000000030b9f0
This causes stack overflow in Oracle JRockit JVM. (It does not cause overflow with Oracle Sun JDK.) Is there a recommended stack size for this use case for JRockit? Is there a way to compute it roughly?
Platform Itanium 64 (linux)]
java version "1.5.0_06"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_06-b05)
BEA JRockit(R) (build R26.4.0-63-63688-1.5.0_06-20060626-2259-linux-ia64, )
mp

How do I found default heap size, stack size for the
thread, number of threads per jvm/process supported ?The threads is OS, OS install and jvm version specific. That information is also not useful. If you create the maximum number of threads that your application can create you will run out of memory. Threads require memory. And it is unlikely to run very well either.
The default heap size and stack size are documented in the javadocs that explain the tools that come with the sun jdk.
and how the above things will vary for each OS and how
do I found ? Threads vary by OS, and OS install. The others do not (at least not with the sun jvm.)
If I get "OutOfMemoryError: Unable to create new native thread" Most of the time it indicates a design problem in your code. At the very lease, you should consider using a thread pool instead.
I found in one forum, in linux you can create maximum
of 894 threads. Is it true ?Seems high since in linux each thread is a new process, but it could be.

How do I get the "Themes" (Designs) for arranging my photos to email them for my iPhoto?

How to get "Themes" (Designs) for arranging my photos to email them in my iPhoto?
Thank you

Hello bendercm, '''try Firefox Safe Mode''' to see if the problem goes away. Safe Mode is a troubleshooting mode, which disables most add-ons.
''(If you're not using it, switch to the Default theme.)''
* On Windows you can open Firefox 4.0+ in Safe Mode by holding the '''Shift''' key when you open the Firefox desktop or Start menu shortcut.
* Or open the Help menu and click on the '''Restart with Add-ons Disabled...''' menu item while Firefox is running.
[[Image:FirefoxSafeMode|width=520]]
''Once you get the pop-up, just select "'Start in Safe Mode"''
[[Image:Safe Mode Fx 15 - Win]]
'''''If the issue is not present in Firefox Safe Mode''''', your problem is probably caused by an extension, and you need to figure out which one. Please follow the [[Troubleshooting extensions and themes]] article for that.
''To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.''
''When you figure out what's causing your issues, please let us know. It might help other users who have the same problem.''
Thank you.

Keep switch channel selected for multiple steps in a scan list

Hi,
I have 3 switches (PXI-2575), one to apply a source to a given line, one to apply a sink, a one to apply a DMM. I have all three switches triggering off each other as well as a DMM (PXI-4070). I apply a source to any given line with the source switch and then cycle through other lines using the DMM switch. Problem is i want to keep the wear on the relays of the source switch to a minimum (for each cycle through the DMM lines I'm selecting same source pin multiple times!). Is there a command for scan lists or some way of setting up the switches so that this can be done?
I thought it might be possible to use the debounce command ';' on its own to signify that i don't want to change the channel selection but this does not appear to work, the DMM times out whilst waiting for a trigger on the second reading. Simplified example scan list that i currently have:
Break Mode: No Action
Source Switch: ch0->com;;;;~ch0->com & ch1->com...
DMM Switch: ch100->com;~ch100->com & ch101->com;~ch101->com & ch102->com;~ch102->com & ch103->com;~ch103->com & ch100->com...
I've also tried selecting the same channel in subsquent scan list entries which flags up error saying explicit connection already exists between the channels.
So is the only possibility just to needlessly wear out the relays?!

Hi leon007,
I can understand your desire to keep the wear on the relays of the Source switch to a minimum. I have a few questions, but we should be able to get the application working without needlessly wearing out the relays.
1. Can I assume you are using NI-SWITCH to program this application? If you are using the NI-DAQmx Switch API, please let me know.
2. When you state "I have all three switches triggering off each other as well as a DMM", can I assume (leaving out the Sink switch for now) the scan advanced output of the Source switch (TTL0) is sent to the trigger input of the DMM switch (TTL0), the scan advanced output of the DMM switch (TTL1) is sent to the trigger source of the DMM (TTL1), and the measurement complete destination of the DMM (TTL2) is sent to the trigger input of the Source switch (TTL2)?
3. If you are still having troubles after this post, I would like to know the following so I can assist in testing the issue: What versions of NI-DAQmx and NI-SWITCH do you have installed?
OK, that's it for my questions. Now for yours. Unfortunately, the debounce command ';' didn't work because it is simply a dummy entry - without creating a connection no scan advanced signal will be sent. I've noticed this is not documented well in our help file, and I apologize for that. However, attempting to create a connection where one already exists should be an error. Either the user is attempting to redundantly connect channels (which shouldn't happen if niSwitch Get Relay Position is used), or there is a driver issue.
To keep the relay wear to a minimum, I want to suggest a couple of ideas.
1. Use only one trigger line for the DMM's measurement complete and one trigger line for all the switches scan advanced outputs. To use this option, it cannot matter in your application which switch operates first, and which operates last. The switch that always makes a connection (the DMM switch) will send a scan advanced output trigger with a set scan delay (configured in niSwitch Configure Scan Trigger) that should accommodate for all the switches. This option may add delay in your application, but you will save relay life.
2. Use the DAQmx Switch API and the '&&' command between seperate switch connections. In the DAQmx Switch API, you use just one scan list for all switch modules. For example, we would perform the example scan list entries you provided with the following scan list:
/Source/ch0->com && /DMM Switch/ch100->com; ~/DMM Switch/ch100->com & /DMM Switch/ch101->com; ~/DMM Switch/ch101->com & /DMM Switch/ch102->com; ~/DMM Switch/ch102->com & /DMM Switch/ch103->com; ~/Source/ch0->com & /Source/ch1->com && ~/DMM Switch/ch103->com & /DMM Switch/ch100->com...
The above connects the Source switch CH0 to COM, waits for the relays to settle, connects the DMM switch CH100 to COM, sends the scan advanced output signal, and waits for the trigger input before executing the next scan list entry. This method will keep an order to the madness, as you will have the power to decide which switch operates first, and which operates last.
Let me know if I assumed anything incorrectly or if neither option works for you!
Chad Erickson
Switch Product Support Engineer
NI - USA

Can't write to flash1: in a 3 switch stack

I have a 3 switch stack at a remote office consisting of a 48 port 3750X, 24 port 3750X PoE, and a 48 port 3750v2. Currently this stack is functioning normally and is running 12.2(55)SE3 (universal on the X's, ipservices on the 3750v2). I want to upgrade to SE8 so that's 12.2(55)SE8 as I see in the release notes there are some vulnerabilities fixed in SSH.
For the life of me, I cannot copy the new file to flash1: which is the 24 port 3750X PoE. This switch has 20 IP phones and 2 Cisco Access points on it and is vital to the branch office. I have spare non poe switches but not spare poe switches (looking for approval), so go figure I am having the issue with the flash memory on this switch.
If I try to tftp the file c3750e-universalk9-mz.122-55.SE8.bin to flash1, I get Error opening flash1:/c3750e-universalk9-mz.122-55.SE8.bin (Bad file number).
I can get the file tftp'd to flash2 (the 48 port 3750X) fine, but if I try to copy it from flash2 to flash1, I get the same error (bad file number).
Cisco TAC reccomened format flash1: , so I tried that and get Error formatting flash1 (Device or resource busy). OK so on my own I figure maybe its corrupt, lets run fsck /test flash1: and see. NOPE can't run that either... Error fscking flash1: (Device or resource busy). Ok now lets see if any other sessions are hung where something or someone has locked flash1... so I run systat and I am the only user on the switch stack. Ok so no one else has a hung connection that may have had a write in process frozen.
So what should I do? The uptime is 30 weeks, 23 hours, 3 minutes. The last switch in the stack, the regular 3750v2 has an uptime of 15 weeks, 1 day, 20 hours, 28 minutes because it was added to the stack back then.
Anyway the network is fine and functioning... just looking to standardize all our 3750's to the 122-55.SE8 release because it is the one IOS that we've had the best luck with.

Well after a few days of SILENCE from Cisco TAC, they got back to me again and said to reseat the flash again! I said tell me how to reseat the flash when it is soldered onto the motherboard of a 3750X switch?
So they responded with this and they are going to replace the switch:
The error message( Error opening flash1:/c3750e-universalk9-mz.122-55.SE8.bin (Bad file number)) indicates that the flash is not visible,
This issue can be solved by the following steps :
Reseat the flash if you cannot,
Format the flash if you cannot,
Replace the device(hardware failure)
As I can see from this case that the device is unable to format the flash, the only way to solve the issue is to replace the switch 1,
I can tell you support has really gone downhilll. So much that I am considering Extreme Networks, Arista and Broacade for an upcoming 10gbps switching project. Another case we had with them was due to a random switch stack crash on 12.2.58SE2. Well they had the entire show tech ouput and they still reccomended to move to 15.0.2SE4. Well that was BAD advice. When you have 6 3750V2's and 3 3750X's in one stack of 9, release 15 doesn't have enough memory to even run a console. We had to break the stack and one by one go to 12.2.55SE8. I don't know what Cisco is thinking. How can they say oh run this release but then they see its a huge mixed breed stack with a large configuration and they don't take memory into consideration? I even asked are you sure, and they said yes we assure you this release will solve your problems.
So between that bad advice and this bad advice, I am really discouraged at throwing more money into "SmartNet" contracts.

2 Switch stack Design for redundancy

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