MikroTik

SYSTEM : P4 / 1.8 GHz 512 MB ram MT 2.9.31 on a CF card

concurent users ~ 15 , 8 VPN (PPTP)

ping on local interface ( 10/100 Mbit lan) :


C:\Documents and Settings\Administrator>ping 10.100.13.1 -t

Pinging 10.100.13.1 with 32 bytes of data:

Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time=145ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time=63ms TTL=64
Reply from 10.100.13.1: bytes=32 time=312ms TTL=64
Request timed out.
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time=260ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Request timed out.
Request timed out.
Reply from 10.100.13.1: bytes=32 time=89ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64
Reply from 10.100.13.1: bytes=32 time<1ms TTL=64

Ping statistics for 10.100.13.1:
Packets: Sent = 27, Received = 24, Lost = 3 (11% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 312ms, Average = 36ms

WHAT COULD THE REASON BE , AFTER RESTART PING GETS OK FOR SOME TIME THEN COMES THE SAME ?

Take a look at your system resources when the ping time starts to increase, I see this problem when I have an abuser and my Routerboard CPU goes to 100%. But with only 15 users, it likely is something else as I'm running 500+ clients through my Routerboard 230 only get that problem with abusers.

Hopefully that helps you trackdown the problem.

Seccour thanks for quick reply but all my clients are friends of mine and have no idea of TCP/IP hacking or smth like that the lines are mostly used for VoIP ( SKYPE ) . and no suspicios traffic or even packets seen ... CPU is like 3%~5% (on P4 normaly ... )

i had the same problem with the lan and wan interface but it was for a simple queue it was without target upload and target download it was in blank

also a bad network card or cable could be at fault. and yes, check firewall and queues.

I think you should check arp deceive in the local area !