On Fri May 30 2008 13:37:12 Dotan Cohen wrote: > > It's your ISP's job to find out why the connection is timing > > out. If they can't or won't, trying to explain "mtr" to them > > isn't going to help. (BTW, your "mtr" was bad but not awful > > because of the "2.3%" line.) > > Could you elaborate on that? I've stfw but I'm still not quite > proficient with mtr or computers in general.
If an mtr or traceroute or tracepath, after a sufficient number of iterations, looks like this: HOP1 20% packet loss HOP2 30% packet loss HOP3 2% packet loss ... - it means that 98-100% of packets are getting to HOP3 and back, which means that the packet loss at the earlier hops is probably due to high CPU loads or ICMP rate limiting rather than fundamental loss of packets in transit. (But there could be more esoteric causes such as errors in diverse return routes.) > > If you really have to use "mtr", first of all compare a regular > > "mtr" with a "mtr -i 10" to see if DOS attacks (and "mtr") are > > being filtered. > > I suppose that I don't _have_ to use mtr but it is the tool that I've > heard of. I changed the interval time to 10 seconds like you mention, > but I don't see where that helps. If you're sending N test packets per second you may be running afoul of an ISP's anti-DOS-attack filters. By comparing those results with results obtained at N/10 test packets per second, you can determine whether this is a likely explanation. > Is there a resource that you could recommend that I read to learn to > be more proficient with mtr? Written for silly end-users like me? Sorry, I don't know of one. "mtr" is a tool. A rough analogy would be me asking for instructions on how to use a screwdriver when my car is broken. I would need to understand how the car's systems work in order to understand how to find out what is wrong and how to fix it. There are lots of good introductory networking courses available. I recommend Cisco's CCNA but you might find others more to your taste. I won't pretend that CCNA (or even CCNP) will explain the full implications of "mtr" output, but they'll give you enough background that you will then be able to understand the implications. --Mike Bird -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
