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What can happen when the TTL is 1?
When a labeled packet is received with a TTL of 1, the receiving LSR drops the packet and sends an ICMP message “time exceeded” (type 11, code 0) to the originator of the IP packet. This is the same behavior that a router would exhibit with an IP packet that had an expiring TTL.
Can a switch have a loopback interface?
By default, each switch has an internal loopback interface ( lo0 ) with the IP address 127.0. 0.1. Each loopback interface can have multiple IP addresses. Routing protocols, such as RIP and OSPF, advertise the configured loopback addresses throughout a network or autonomous system.
Does a switch decrement TTL?
Yes correct .. TTL value dosent decremented by a switch. TTL field in IP datagram is set by the sender and decremented by every router on the route to its destination.
What is TTL hop limit for IP packages?
Time to live (TTL) or hop limit is a mechanism which limits the lifespan or lifetime of data in a computer or network. TTL may be implemented as a counter or timestamp attached to or embedded in the data. Once the prescribed event count or timespan has elapsed, data is discarded or revalidated.
Do switches affect TTL?
For every router that I insert in between my computer and the router that connects to the internet, the TTL value goes down by one. However, inserting a switch or a hub does not have any effect on the TTL value.
What is a good TTL ping?
The TCP/IP specification recommends setting the TTL field for IP packets to 64, but many systems use smaller values (4.3BSD uses 30, 4.2BSD used 15). And to quote RFC 1700: The current recommended default time to live (TTL) for the Internet Protocol (IP) is 64.
What is TTL 63 in Ping?
The other device you ping sets the TTL to 63. So when it gets to you, the value is 47. 255-239=63-47=16. If you want to be sure about the number of hops between you and the target, use traceroute.
Why is TTL always 1 in IP packets?
However if we enable EBGP between the two using directly connected IP, we see EBGP establishes, even though TTL value is 1 in IP packet. We see R1 or R2 does not discard message even though TTL =1 ,as they would normally do for other packets.
Can You Ping the loopback interface on switch 1?
Currently, I am able to ping the loopback interface on switch 1 but not on switch 2 from any computer in the 2 VLANS i created. i have enable IP routing on both switches. I can ping the computers both vlans and the vlan ip addresses. I can also ping the switch 2 loopback interface from switch 2 but not from anywhere else.
What can a loopback interface be used for?
As a result, a loopback interface is useful for debugging tasks since its IP address can always be pinged if any other switch interface is up. You can use a loopback interface to establish a Telnet session, ping the switch, and access the switch through SNMP, SSH, and HTTP (WebAgent). A loopback IP address can be used by routing protocols.
What’s the maximum IP address for a loopback interface?
The maximum number of IP addresses supported on a switch is 2048, which includes all IP addresses configured for both VLANs and loopback interfaces (except for the default loopback IP address 127.0.0.1). Each IP address that you configure on a loopback interface must be unique in the switch.