Posts tagged "Cisco"
Cisco Routing - Administrative Distance
Cisco routers are capable of different routing protocols and static and connected routes. Every routing protocol engine has its own distance/metric/weight to decide which route is best. When a routing protocol has chosen its best route, the route is entered into the routing table. The routing engine uses an "adminis...
WScale and Cisco Content Switch CSS.
Problem: Windows 7 clients wait 5 seconds to send simple HTTP requests to a web server behind a cisco CSS content switch. But there is no delay when the client connects directly to a web server behind the CSS. Description: I found one difference between CSS and non-CSS connects: the TCP WSCALE option. When the CSS i...
Cisco IP Phone and NTP
Problem: A Cisco IP phone (in my case 7970G) does not sync with an NTP server. The phone sends an NTP request, receives an NTP response, but does not set its date and time. Solution: It's a known bug of Cisco's IP phone software releases 8.3(3) or higher according to Cisco bug id: CSCso40588. Cisco says that these p...
Windows Network Load Balancing NLB and Cisco Routers/Switches
Problem: Windows NLB IPs are are not reachable through and from Cisco routers and switches. NLB services could be IIS arrays, Exchange CAS arrays, etc. Solution: NLB mode was set to Multicast. In this mode Windows incorrectly uses multicast mac addresses. Set the NLB mode to Unicast and configure static mac address ...
Cisco has weird naming conventions for groups of interfaces
If you want to bind some ethernet interfaces into one logical interface between two ciscos switches you have to configure an interface first: interface Port-channel 1 then add some interfaces into this new interface: interface GigabitEthernet 1/0/1 channel-group 1 mode active and you can check the status with: show ...
L2TP tunnel between two cisco routers
Problem: a Cisco 1941 [15.1(2)T2] (Client) tries to connect to an Cisco7300 [12.3(22)] (Server) using L2TP, but after successful authentication of the client the server drops the connection. Solution: The client tried to authenticate the server, but the server had no password for authentication. Normally only the cl...
Cisco Access Point blocking PPTP
Vienna: 10. August 2011 Problem: A network of some Cisco Access Points AIR-AP1142N-E-K9 connected to an small router works good as expected but when the user tries to connect to en PPTP VPN the connection fails with a time-out. Solution : it was no NAT problem in this case (I fixed this before). Cisco IOS 12.4(21)??...