Why do I have a ping to addresses in one visit for some addresses goes to some does not go?

Question

Computer networks

Есть такая проблема, пинг на адрес 127.2 идет
R1> ping x.x.127.2
PING x.x.127.2 (x.x.127.2): 56 data bytes
64 bytes from x.x.127.2: icmp_seq=0 ttl=252 time=15.266 ms
64 bytes from x.x.127.2: icmp_seq=1 ttl=252 time=9.605 ms
^C
--- x.x.127.2 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max/stddev = 9.605/12.405/15.266/1.925 ms
R1>
Но пинг на адрес 127.252 который находится в одной подсети с 127.2/24 не идет.
R1> ping x.x.127.252
PING x.x.127.252 (x.x.127.252): 56 data bytes
^C
--- x.x.127.252 ping statistics ---
4 packets transmitted, 0 packets received, 100% packet loss
R1> The
trace goes to the first address, to the second it closes on 98. This is the PE of our well-known green provider.
We have BGP configured.
R1> traceroute xx127.2
traceroute to xx127.2 (xx127.2), 30 hops max, 40 byte packets
1 x.212.35.2 (x.212.35.2) 1.827 ms 3.067 ms 2.335 ms
2 x.212.35.98 ( x.212.35.98) 21.351 ms 5.055 ms 8.723 ms
3 x.212.35.97 (x.212.35.97) 7.775 ms 8.665 ms 7.711 ms
4 xx127.2 (xx127.2) 11.535 ms * 9.5 tracero60 ms
R1>7ute.x2 252
traceroute to xx127.252 (xx127.252), 30 hops max, 40 byte packets 1 x.212.35.2
(x.212.35.2) 3.099 ms 1.490 ms 1.413 ms
) 9.437 ms 9.413 ms 16.050 ms
3 * * *
^C
R1>
There are routes.
R1> show route xx127.2
inet.0: 14595 destinations, 21231 routes (11541 active, 0 holddown, 3160 hidden)
+ = Active Route, - = Last Active, * = Both
xx127.0/24 *[BGP/170] 1d 01:35:34, localpref 200
AS path: 65494 3524 I
> to x.212.35.2 via ge-0/0/0.0
R1> show route xx127.252
inet.0: 14595 destinations, 21231 routes (11541 active, 0 holddown, 3160 hidden)
+ = Active Route, - = Last Active, * = Both
xx127.0/24 *[BGP/170] 1d 01:35:37, localpref 200
AS path: 65494 3524 I
> to x.212.35 .2 via ge-0/0/0.0
R1>
Who will tell you what to do and where to dig? The equipment we have is Juniper SRX550 at the CE of the head office and Juniper SRX210 at the CE of the additional office.

Answer 1

Are 127.2 and 127.252 exactly on the same network? Those. exactly on both devices /24 ? If not, compare the routing tables on them. The fact that for you they are one / 24 - still does not say anything

Answer 2

And what about routes on pieces of iron 127.2 and 127.252 (or routers connected with them)? The as path for them is also interesting. Runs di traffic in case of static routes on all pieces of iron.?

Answer 3

But the ping to the address 127.252 which is in the same subnet with 127.2/24 does not work.

Why do you think this host should be responding to pings?
Who owns this address (server, router)? In any case, check the access lists (firewall filter) along the traffic path, check the filtering on firewalls, check the availability of the problem host using other protocols (does it send TCP RST, for example, in response to TCP SYN), also check its availability with device closest to it.

Answer 4

Probably a joint with a mask. Perhaps the one who announces the network xx.xx.127.0/24 announces it not with /24, but with /25. Then it is logical that the upper half of the network will be inaccessible to you (host addresses from 127.128 and above).

Answer 5

start with the classics - what about routing on an inaccessible host and whether it blocks icmp in principle.