...yet if I look at one of the routes that the switch doesn't seem to have a specific routing entry for, it appears to have it:
PPFX_X37_274#sh ip ro 10.73.16.251 Routing entry for 10.73.16.0/24 Known via "ospf 1", distance 110, metric 25201, type inter area Last update from 10.4.112.234 on Vlan900, 17:00:20 ago Routing Descriptor Blocks: * 10.4.112.246, from 10.200.1.216, 17:00:20 ago, via Vlan900 Route metric is 25201, traffic share count is 1
Q. Why does it still know a precise route if it says it is covered by 10.73.0.0/16 in the above command?
Q. What is the exact impact of packets being routed to this subnet via the 3750 given that it is stating it doesn't have enough resources to hold this route?
I'm hoping it doesn't mean that every packet is effectively process switched each time by the switch CPU (adding latency)....
I understand the resolution is to change the SDM template to routing to allow for extra resources to be assigned for routing, but want to understand the exact current impact this causes.
moving to routing template can accomodate 11000 routes.
but you can see reduced other TCAM resources
You need to consider what you really need.
prefixes that are not installed in the TCAM and are not covered are process switched for sure causing high cpu usage.
If you don't need the component routes find a way to get only the aggregate routes
what can happen is that component route has a different next-hop and the device is using the next-hop of the aggregate route this can even cause connectivity problems if the major network is partiotioned. (just an example I don't know your environment...)
So more then a perfomance issue you can face suboptimal routing or even connectivity problems if passing traffic to some device that wll try to route it back to this device.
The 3750 is in Area0 and we are already performing some summarisation, but can not improve this further.
PPFX_X37_274#sh ip ro summary IP routing table name is Default-IP-Routing-Table(0) IP routing table maximum-paths is 32 Route Source Networks Subnets Overhead Memory (bytes) connected 0 2 232 304 static 0 0 0 0 ospf 1 65 2155 32768 337440 Intra-area: 122 Inter-area: 1308 External-1: 630 External-2: 160 NSSA External-1: 0 NSSA External-2: 0 internal 22 25784 Total 87 2157 233000 363528
My understanding is the desktop default allows for upto 2k unicast routes (indirect), and above shows 2,157 subnets suggesting I've just hit the threshold... SDM prefer routing allows for 8k indirect routes (I guess this means non-attached networks??). So a change of template should resolve this problem.
FYI - I am seeing packet loss and high latency for only a subset of subnets across this switch, so I guess this is the cause. The switch is also running at around 35% CPU utilisation.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.