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Network Operations





Network Operations includes asset management, help-desk supervision, security and user policies, infrastructure administration and anything else that affects the operation of your network. Discussions will include those of best practices in platforms, configurations, performance, security and accounting.

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I’m hoping to get some ideas on this one. I’m having some intermittent latency and sometimes dropouts on the network, which consists of mostly Cisco SX300 switches.

When the latency or dropout happens, the CPU utilisation of the core SG300 Switch would be over 40%. I have been told the issue is caused by spanning tree and turning global spanning tree off on the core switch does help, however, I think it is not the spanning tree or it is more that just the spanning tree.

What other things could I look into in finding the cause?

Any help appreciated!

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I have problem PXE boot from Microsoft surface 4 (UEFI) to connect to WDS server (Windows 2016). I have updated surface firmware and OS patches etc.. Getting below error

NBP filename is boot\x64\wdsmgfw.efi
NBP filename is 0 Bytes
PXE-E23: Client received TFTP eror from server

All other machines except MS surface are working fine. What step need to do resolve this issue.
Hi all,

   I have a very annoying problem in which everything works like a dream, and one application is hanging almost certaintly die to lost file handles.

   The network is exemplary; certified Panduit, server 2012 R2, almost everything on the network is new and now I installed 7 new HP computer with Windows 10.

   What happens is that the application we have that runs on a flat-file database (Clarion) shared on local server is hanging up. For testing purposes on old Win 7 machines everything is working stable.

   I am pulling my hair on this one, and I don't know how to proceed.

   I tried max power management, disabling Green Ethernet, disabling AV program and Firewall, disabling all non ms services, etc. All the time the app behaves the same.

   Any ideas or diagnostic procedures are Welcome.
Need to recover passwerd for cisco switch 4507R-E without removing the configuration
I have to develop a Runbook that provides operational procedures for obtaining security certs.  Can someone provide me with a template of a runbook or a website where I can find a template?  

Dear experts,

I am new to the DNS and DNS load test. Now i have task to test Load Test on two BIND9 servers [RHEL6]. I had googled it and i found dnspref is good tool to evaluate throughput and latency. However, I need a script to do this task. I will be very helpful for me if any one share the info.

Hi ,

we have subsidiary company with around 150 Users . it is linked to us (HO ) over IPVPN (1 MB)  and services getted from Us are :

1- CISCO IP telephone ( currently around 75 Users)
2- ERP ( about 50 USers)

thier existign Setup :

1- Domain COntroller ( seprate totally from us ) + Antivirus server ( 1 physical box)
2-finance system
3-Backup Server
4-Sonicwall NSA2600
7-Router for IPVPN

the managment is thinking to host the setup for the subsidary company so my questions are:

1- how I can do the proper sizing for the link ? so i ensure the users are not feeling slowness
2-what equipment should i move from there and what i should not ? best desing fro myour experince
3- how the internet should be provided to thier users ? from us or locally ?
4- what are the adv and disadvanage for such plan? should we recommend this plan or let them continue as they are
5- risks?
6- what are the pre requisits needed in the HO Data Center for hosting those equipment
I am employed in one ISP,  I am trying to do redudant link between my pop Cisco switch to my customer end MIKROTEK Router but it cause loop of the network,  any body have solution to do work proper RSTP between MIKROTEK & CISCO switch???
Hi Guys,

 I am trying to use hyper-v extended port acl's as a basic form of firewalling for vms on hyper-v server 2016

My goal is simply to limit incoming connections while generally allowing outgoing traffic (and return traffic).

In essence we are allowing incoming http(s) and dns replies. All outgoing tcp traffic is marked as stateful.

We use the following acl's (cleaned up slightly for readability)
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Deny" -Direction "Inbound" -Weight 20
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Allow" -Direction "Inbound" -Weight 30 -Protocol 1
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Allow" -Direction "Inbound" -LocalPort 80  -Protocol "TCP" -Weight 60
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Allow" -Direction "Inbound" -LocalPort 443  -Protocol "TCP" -Weight 70
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Allow" -Direction "Inbound" -RemoteIPAddress "" -RemotePort "53" -Weight 130
Add-VMNetworkAdapterExtendedAcl -VMName "web" -Action "Allow" -Direction "Outbound" -Protocol "TCP" -Stateful $True -Weight 150

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The issue is as soon as the last stateful entry is added significant latency is observed to the point of things becoming useless.

In the cisco switch acl world you would simply look for the established flag for the packet.

Is there a way we can achieve the same here without incurring these severe performance penalties? Am I doing it completely wrong?

thanks for any insight.
Dear Experts, please help us this case:

We are using Cisco Router 3925 as the gateway for LAN users, users' IP addresses were NAT overload via the interface that connect to the ISP; however we got a network ( that could not access a website.

If we NAT static a PC inside that network to a static public IP address (or a pool of public addresses), the PC could access the website; but if we did not NAT static and using NAT overload via gateway interface, PC could not access website.

Do you know why? Please suggest
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I have configured UDP jitter SLA on my test lab. What do the below counters indicate of my connection? Why is there no latency numbers?
How am I supposed to read this?

ip sla 90
 udp-jitter 65050 num-packets 20
 request-data-size 100
 tos 128
 frequency 30
ip sla schedule 90 life forever start-time now

Test_Lab_Router_Place#sh ip sla statistics  de
IPSLAs Latest Operation Statistics

IPSLA operation id: 90
Type of operation: udp-jitter
        Latest RTT: 11 milliseconds
Latest operation start time: 12:03:15 cst Wed Feb 21 2018
Latest operation return code: OK
Over thresholds occurred: FALSE
RTT Values:
        Number Of RTT: 20               RTT Min/Avg/Max: 9/11/17 milliseconds
Latency one-way time:
        Number of Latency one-way Samples: 0
        Source to Destination Latency one way Min/Avg/Max: 0/0/0 milliseconds
        Destination to Source Latency one way Min/Avg/Max: 0/0/0 milliseconds
        Source to Destination Latency one way Sum/Sum2: 0/0
        Destination to Source Latency one way Sum/Sum2: 0/0
Jitter Time:
        Number of SD Jitter Samples: 19
        Number of DS Jitter Samples: 19
        Source to Destination Jitter Min/Avg/Max: 0/2/8 milliseconds
        Destination to Source Jitter Min/Avg/Max: 0/1/1 milliseconds
        Source to destination positive jitter Min/Avg/Max: 1/3/8 milliseconds
        Source to destination positive jitter Number/Sum/Sum2: 5/19/119
        Source to destination negative jitter Min/Avg/Max: 

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If a want to measure how much bandwidth a data link is consuming I have to add the upload and download of the link?

How to setup up a new domain Controller.
Dear Expert,

I will shut down my Checkpoint Firewall R77 and Hitachi San (model: HUS130) . Could you please provide a startup and shutdown procedure for Checkpoint and HItachi SAN manual. In addition, Will share your experience for shutdown /startup process. Thanks
My sonicwall is dropping my connection from a second subnet. I understand why, as it is identifying this 96... ip address as a WAN on the LAN. However I just simply want to allow all traffic from that IP to get through. How would I go about configuring the sonicwall?

I tried disabling IP Spoof Checking from the diag.html page, but it refuses to save and only says "there were no changes made".

01/15/2018 12:07:25.640      Alert      Intrusion Prevention      IP spoof dropped      96.67.165.X, 49873, X1      209.63.225.X, 80, X1      


We are running an intranet in our organization...now we are thinking to provide the access of our intranet to the users even through their mobile..How can we do this... and is this possible?

Thanks in advance,
Srikanth Nandyala.
Hey guys,
We have just acquired a client that uses Cisco stuff.  I am looking at the show run file for one of their devices.  I see non default vlans added to the ports, but I don't see any list of vlans.  Somewhere at the top of the file I see, "vlan internal allocation policy."  The stuff that I am reading about it is confusing, but it seems that what this is doing is importing vlans from another device.  Is this correct?
i.ve scom 2016 and need to specify some service that i need to show using the visio to make dashboard. so if i need to check health of the DNS service in my 3 domains how can i do that and shall i choose. also if  i need to check the status of my DHCP subnets can i do that?
i'm using visio 2013 and the scom addin installed but it's for system centre 2012 does it make any effect?
also if i need to just click on the service from the visio should it gives me the status of this object only?
On a Cisco ASA, how can send only logging from a single access control list rule to a syslog server.?
Configuration with ASDM please

- Jac
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We have an old Asterisk (v.2.x) phone server in our office.  I'm new to the system and need to change an extension number from a rapid busy signal to a working extension.  Also, we have several extension that simple hang-up when dialed (no tones of any sort).  How do we edit those extensions?

I'm new to Linux, but I've figured out how to browse directories and edit conf files.
What is the best option for a router or managed switch for a new fiber connection we have coming into our building?

Any recommendations other than a Cisco switch?

Basically we have a tail coming in with 50/50 fiber and 2 ip’s and 2 businesses need to leverage off it, our business and another.

Both businesses are separate but contributing to the connection and aside from QoS just need something to be able to push 1 internet ip to 1 lan and 1 ip to another.

Was assuming a managed switch or router with a vlan switch to 1 port and a vlan to another. Each business will have their own router and firewall from that point

No data can cross.

So was just looking for the best option and what unit would be reasonable whether a router or switch and just setup vlans

Any assistance greatly appreciated.
I want to know how to integrate Chocolatey into SolarWinds N-Central?

Any suggestions would be appreciated.

How yo untag port example 40 in Cisco firewall?

Currently we have situations port 40 was in the server vlan.

If we untag port 40 in the switch It might compromise security issue.

is there a workaround Solutio to untag port 40.
Hi Guys

I have Two Cisco Router r1,r2 both of them have the same getaway , i need to Achieve the high availability between the two so if r1 down .the r2 should be up and replace r1

see attached the network design


Simple network Diagram

Let's say I'm an ISP and I lease a 10G transport pipe to an IX (Frankfurt or Amsterdam), with the purpose of buying transit from 2 different tier 1 providers (2 resellers, probably) and peering with content providers.

What happens inside the IX?

Do I get one switch port and I have to rent rack space for my own equipment there? The peerings are physical, with cables between my switches and the peer switches?

Or I only get a VLAN and the peerings are inside the IX main router/switch? And I route the traffic from my VLAN to my peer's VLAN?


I've googled for the past days, but I'm still confused. Anyone has real world experience with this?

Thank you.

Network Operations





Network Operations includes asset management, help-desk supervision, security and user policies, infrastructure administration and anything else that affects the operation of your network. Discussions will include those of best practices in platforms, configurations, performance, security and accounting.