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Hello All,
I'm setting up a small network of workstations running redhat 9 and unfortunately I cannot get them to ping each other. Here is the basic setup and the things I've tried so far. If anyone can shed some light and tell me what I am missing I'll be more than greatful.
Basically I have 2+ computers that are connected via a 16-port Linksys hub.
The addressing scheme is a class A network, for example
WS 1:
10.0.0.0 0.0.0.0 255.0.0.0 U 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 lo
WS 2:
10.0.0.0 0.0.0.0 255.0.0.0 U 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 lo
The troubleshooting I've done so far is:
1. disabled Iptables and all firewall
2. tried adding static routes from one computer to the other and that doesn't seem to alleviate the problem.
3. I verified the interfaces on each workstation is up by pinging its eth0 and loopback
4. verified that proc/sys/net/ipv4/icmp_echo_ignore_all
is set to 0
5. cabling and hub is good, all are brand new
I'm not sure what else I could be doing wrong since the topology is very simple and the ip assignments are fine.
I ran my IPs through a ip calculator I found online and it verified the mask should be 255.0.0.0 for the class A addresses. I also fiddled with the mask and changed it to 255.255.255.0 like you said and that didn't work in the past.
Regarding your comment about the gateway, should I set up one workstation as a dhcp server? I'm trying to get away from the dhcp service and just have everything talk peer to peer. The reason I use a 0.0.0.0 gateway is to indicate the workstations are directly connected. I'm really not sure how to set up a gateway that provides static and if you can provide more info on that I'll give it a try.
I have a hub so I'll stick to the 0.0.0.0 gateway like you said.
I think the 192.168.0.0 - 192.168.255.255 is the class C net and
10.0.0.0 - 10.255.255.255 is the class A net.
Given that I think my addressing scheme is correct and I assume that my workstations should be able to ping each other. But pings are returning "Destination host unreachable".
3. Private Address Space
The Internet Assigned Numbers Authority (IANA) has reserved the
following three blocks of the IP address space for private internets:
10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
We will refer to the first block as "24-bit block", the second as
"20-bit block", and to the third as "16-bit" block. Note that (in
pre-CIDR notation) the first block is nothing but a single class A
network number, while the second block is a set of 16 contiguous
class B network numbers, and third block is a set of 256 contiguous
class C network numbers.
If I understand the OP intent, he has simply elected to use a "classfull" netmask (vs. classless). Granted, thats alot of hosts (256^3) that can be defined - but in his test environment, he should still be able to ping the other hosts on the 10.0.0.0/8 network address. Even without the default route defined.
Originally posted by scowles huh? A cut/paste from the rfc1918
Code:
3. Private Address Space
The Internet Assigned Numbers Authority (IANA) has reserved the
following three blocks of the IP address space for private internets:
10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
We will refer to the first block as "24-bit block", the second as
"20-bit block", and to the third as "16-bit" block. Note that (in
pre-CIDR notation) the first block is nothing but a single class A
network number, while the second block is a set of 16 contiguous
class B network numbers, and third block is a set of 256 contiguous
class C network numbers.
If I understand the OP intent, he has simply elected to use a "classfull" netmask (vs. classless). Granted, thats alot of hosts (256^3) that can be defined - but in his test environment, he should still be able to ping the other hosts on the 10.0.0.0/8 network address. Even without the default route defined.
That's what I was thinking too scowles. All the workstations are directly connected via the hub and I should be able to ping. But it doesn't seem as if the computers "see" each other. The workstations run redhat linux 9 so there's no windows involved. phatboyz makes a good point about possible firewall issues and to a certain extent I accounted for that by turning off iptables but something else may be running. I'm not too familiar with the firewall services on redhat 9 so if anyone can tell me how to detect which firewall service is running and how to turn it off that would be great.
Before I'm using Slackware 10 as my NAT to the rest of my XPs until I replaced it now with OpenBSD. But OS here is not an issue. I used private IP address under class C (192.168.1) since I need to connect to the internet via my ADSL. As long as your NICs are all configured properly I don't see any reason that you could't ping each other. If you just intend to make a small LAN, simply give your NICs IP addresses such as: WS1: 192.168.0.1, WS2: 192.168.0.2, so on.
If after confirming that everything are configured as it should be, try to check your cables pairing. I mean the termination on both ends. It should be straight according to T568-B or T568-A. Below is the T568-B wire mapping or the pin assignments in your RJ-45 connector. 10/100Tx uses only Pairs 1 and 2 (pins 1 & 2; 3 & 6) respectively. 1000T (Gigabit) will use all of the pairs. Ofcourse the minimum cable now is Category 5 Enhanced.
End --- to --- End of cable
1. White-Orange-------------------------1. White-Orange
2. Orange----------------------------------2. Orange
3. White-Green---------------------------3. White-Green
4. Blue--------------------------------------4. Blue
5. White-Blue------------------------------5. White-Blue
6. Green------------------------------------6. Green
7. White-Brown----------------------------7. White-Brown
8. Brown------------------------------------8. Brown
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