hung up troubleshooting packet discards

Posted by Chris Satola on Server Fault See other posts from Server Fault or by Chris Satola
Published on 2012-04-05T16:03:17Z Indexed on 2012/04/05 17:34 UTC
Read the original article Hit count: 305

Filed under:

cisco

|

packetloss

I realize my question is generic, but hopefully someone may have some guidance for me. My network consists of Cisco switches. I am seeing a significant amount (upwards of millions of packets per day) transmit drops between two switches. One being a 3750 and the other a 3560. The peak throughput of this link is only upper 400Mbps, so it shouldn't be a bandwidth issue.

At this point, I am sort of clueless where to look or what tools I can use to determine what packets are dropping and why. I can setup a SPAN port on that link and wireshark it, but I don't know if that could tell me anything. Does anyone have any suggestions? Thanks in advance.

© Server Fault or respective owner

Related posts about cisco

Cisco Unifed Communication integration for Microsoft Lync crashes on Remote Desktop services 2008 R2!

as seen on Server Fault - Search for 'Server Fault'
Hi everybody i have deployed office communication server 2007 R2 and communicator 2007 R2 and i made integration with Cisco Unified Communication Manager 7.1 in my network, i also uses Remote Desktop Servers 2008 R2 for Thin Client Computers, now that i installed Cisco UC integration client for communicator… >>> More
Cisco Unified Communication integration for Microsoft Lync crashes on Remote Desktop services 2008 R2!

as seen on Server Fault - Search for 'Server Fault'
Hi everybody i have deployed office communication server 2007 R2 and communicator 2007 R2 and i made integration with Cisco Unified Communication Manager 7.1 in my network, i also use Remote Desktop Servers 2008 R2 for Thin Client Computers, now that i installed Cisco UC integration client for communicator… >>> More
Cisco Prime NCS not starting

as seen on Server Fault - Search for 'Server Fault'
I have received the Cisco Prime OVA file and which we placed onto an Oracle virtual environment. We turn the VM on and the CLI boots, When we try to start the NCS service we get errors. HOSTNAME/USER# ncs start Starting Network Control System... Exception in thread "main" java.lang.NullPointerException … >>> More
how to set port forwarding on a cisco 881 router (with cisco configuration professional)

as seen on Super User - Search for 'Super User'
I recently got a cisco 881 router for work and I have everything working except port forwarding I want to forward all incoming port 80 requests to 10.10.10.60 and all incoming port 53322 requests to 10.10.10.40 im using cisco configuration professional and im not sure where to find this option thanks… >>> More
Cisco: Site-to-site VPN with cisco 878 and ASA weirdness

as seen on Server Fault - Search for 'Server Fault'
I currently have 2 sites, both connected to each other through 2 firewalls / routers in a site-to-site VPN. Pinging from server to server (Using 2mb/2mb SDSL) through that VPN obviously works, however, at one site, we have another internet connection (7m/400k ADSL), and only the link between the two… >>> More

Related posts about packetloss

Packet loss rate with iperf and tcpdump

as seen on Server Fault - Search for 'Server Fault'
I tested a line for its link quality with iperf. The measured speed (UDP port 9005) was 96Mbps, which is fine, because both servers are connected with 100Mbps to the internet. On the other hand the datagram loss rate was shown to be 3.3-3.7%, which I found a little too much. Using a high-speed transfer… >>> More
unexplainable packet drops with 5 ethernet NICs and low traffic on Ubuntu

as seen on Server Fault - Search for 'Server Fault'
I'm stuck on problem where my machine started to drops packets with no sign of ANY system load or high interrupt usage after an upgrade to Ubuntu 12.04. My server is a network monitoring sensor, running Ubuntu LTS 12.04, it passively collects packets from 5 interfaces doing network intrusion type… >>> More
What is causing a vm to exhibit packet loss?

as seen on Server Fault - Search for 'Server Fault'
We have a pretty nice piece of hardware set up to run multiple virtual machines in vmware and one of the vm's is an instance of Windows Server 2003 running SQL Server 2005. For some reason we occasionally see 10-20 seconds of straight packet loss to this machine from remote machines (my workstation)… >>> More
fast way to find network user computer on domain hogging all wan bandwidth

as seen on Server Fault - Search for 'Server Fault'
i have a network of about 40 domain users and i have huge latency wan issues, like 1400ms for google.com pings. I have noticed that the problem goes away after everyone goes home for the day. I would like to know if i should use something like a hub with wireshark on the router or modem to see if… >>> More
ISA Server dropping packets as it believes they are spoofed

as seen on Server Fault - Search for 'Server Fault'
We have ISA Server 2004 running on Windows Server 2003 SP2. It has 2 NICs - one internal called LAN on 192.168.16.2, with a subnet of 255.255.255.0, and one external called WAN on 93.x.x.2. The default gateway is 93.x.x.1 (our modem). This machine also accepts VPN connections. We are having a problem… >>> More