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<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial>Hi!</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>We're having
occasional problems with ISC dhcpd handing out an incorrect gateway (option
routers) to some clients. This happens only for specific clients and is more or
less persistent for those. The config is somewhat complicated and involves a few
shared networks.</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=824125613-08092011>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>What happens is that
a client in network 123.123.230.0/24 gets a correct IP, the appropriate subnet
mask and all other options, but the gateway is 123.123.235.1, which is in a
totally different subnet and even another shared network! Anybody with a clue
about what's going on out there?</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>Just to give you a
rough idea on the structure, I've filtered out a few lines from the
config:</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>shared-network
eth0{<BR> subnet 192.168.20.0 netmask
255.255.255.0 {<BR> subnet
123.123.224.0 netmask 255.255.255.0
{<BR> subnet 123.123.236.0 netmask
255.255.255.0 {<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>shared-network
BSR1CM {<BR> subnet 172.16.0.0 netmask
255.255.252.0 {<BR> subnet 172.16.8.0
netmask 255.255.255.0 {<BR>shared-network BSR1CPE
{<BR> subnet 123.123.225.0 netmask
255.255.255.0 {<BR> subnet
123.123.226.0 netmask 255.255.255.128
{<BR> subnet 123.123.226.128 netmask
255.255.255.192 {<BR> subnet
123.123.226.192 netmask 255.255.255.224 {<BR>shared-network BSR1MTA
{<BR> subnet 123.123.226.224 netmask
255.255.255.224 {<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>shared-network
BSR2CM {<BR> subnet 172.17.0.0 netmask
255.255.252.0 {<BR> subnet 172.17.4.0
netmask 255.255.252.0 {<BR> subnet
172.17.8.0 netmask 255.255.252.0 {<BR>shared-network BSR2CPE
{<BR> subnet 123.123.227.0 netmask
255.255.255.0 {<BR> subnet
123.123.228.0 netmask 255.255.255.128
{<BR> subnet 123.123.228.128 netmask
255.255.255.192 {<BR> subnet
123.123.228.192 netmask 255.255.255.224
{<BR> subnet 123.123.228.224 netmask
255.255.255.224 {<BR>shared-network BSR2MTA
{<BR> subnet 123.123.229.0 netmask
255.255.255.0 {<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>shared-network
BSR3CM {<BR> subnet 172.18.0.0 netmask
255.255.252.0 {<BR> subnet 172.18.4.0
netmask 255.255.252.0 {<BR> subnet
172.18.8.0 netmask 255.255.252.0 {<BR>shared-network BSR3CPE
{<BR> subnet 123.123.230.0 netmask
255.255.255.0 {<BR> subnet
123.123.233.0 netmask 255.255.255.0
{<BR> subnet 123.123.231.0 netmask
255.255.255.0 {<BR>shared-network BSR3MTA
{<BR> subnet 123.123.232.0 netmask
255.255.255.0 {<BR> subnet
123.123.234.0 netmask 255.255.255.0 {<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>shared-network
CASACM {<BR> subnet 172.19.0.0 netmask
255.255.240.0 {<BR>shared-network CASACPE
{<BR> subnet 123.123.235.0 netmask
255.255.255.0 {<BR> subnet
123.123.237.0 netmask 255.255.255.0
{<BR> subnet 123.123.238.0 netmask
255.255.255.0 {<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>14:29:20.933479 IP
(tos 0x0, ttl 255, id 5252, offset 0, flags [none], proto UDP (17), length 344)
123.123.230.1.68 > 123.123.224.<BR>42.67: BOOTP/DHCP, Request from
00:19:99:a0:51:13, length 316, hops 1, xid 0x39e50835, Flags
[none]<BR> Gateway-IP
123.123.230.1<BR>
Client-Ethernet-Address
00:19:99:a0:51:13<BR>
Vendor-rfc1048
Extensions<BR>
Magic Cookie
0x63825363<BR>
DHCP-Message Option 53, length 1:
Discover<BR>
Client-ID Option 61, length 7: ether
00:19:99:a0:51:13<BR>
Requested-IP Option 50, length 4:
123.123.233.232<BR>
Hostname Option 12, length 12:
"MyRouter"<BR>
Vendor-Class Option 60, length 8: "MSFT
5.0"<BR>
Parameter-Request Option 55, length
12:<BR>
Subnet-Mask, Domain-Name, Default-Gateway,
Domain-Name-Server<BR>
Netbios-Name-Server, Netbios-Node, Netbios-Scope,
Router-Discovery<BR>
Static-Route, Classless-Static-Route, Classless-Static-Route-Microsoft,
Vendor-Option<BR>
Agent-Information Option 82, length
14:<BR>
Unknown SubOption 2, length
6:<BR>
0x0000: 0013 71e7
68ee<BR>
Unknown SubOption 43, length
4:<BR>
0x0000: ac12 03f5<BR>14:29:21.001405 IP (tos 0x0, ttl 64, id 0, offset 0,
flags [DF], proto UDP (17), length 335) 123.123.224.42.67 >
123.123.230.1.67:<BR> BOOTP/DHCP, Reply, length 307, hops 1, xid
0x39e50835, Flags
[none]<BR> Your-IP
123.123.233.232<BR>
Server-IP
123.123.224.42<BR>
Gateway-IP
123.123.230.1<BR>
Client-Ethernet-Address
00:19:99:a0:51:13<BR>
Vendor-rfc1048
Extensions<BR>
Magic Cookie
0x63825363<BR>
DHCP-Message Option 53, length 1:
Offer<BR>
Server-ID Option 54, length 4:
123.123.224.42<BR>
Lease-Time Option 51, length 4:
600<BR>
Subnet-Mask Option 1, length 4:
255.255.255.0<BR>
Domain-Name Option 15, length 11:
"sweden.se"<BR>
Default-Gateway Option 3, length 4:
123.123.235.1 <<<<-----
WRONG!<BR>
Domain-Name-Server Option 6, length 8:
213.50.29.170,208.67.222.222<BR>
Agent-Information Option 82, length
14:<BR>
Unknown SubOption 2, length
6:<BR>
0x0000: 0013 71e7
68ee<BR>
Unknown SubOption 43, length
4:<BR>
0x0000: ac12 03f5<BR>14:29:21.016281 IP (tos 0x0, ttl 255, id 5256, offset
0, flags [none], proto UDP (17), length 364) 123.123.230.1.68 >
123.123.224.42.67: BOOTP/DHCP, Request from 00:19:99:a0:51:13, length 336, hops
1, xid 0x39e50835, Flags
[none]<BR> Gateway-IP
123.123.230.1<BR>
Client-Ethernet-Address
00:19:99:a0:51:13<BR>
Vendor-rfc1048
Extensions<BR>
Magic Cookie
0x63825363<BR>
DHCP-Message Option 53, length 1:
Request<BR>
Client-ID Option 61, length 7: ether
00:19:99:a0:51:13<BR>
Requested-IP Option 50, length 4:
123.123.233.232<BR>
Server-ID Option 54, length 4:
123.123.224.42<BR>
Hostname Option 12, length 12:
"MyRouter"<BR>
FQDN Option 81, length 15:
"MyRouter"<BR>
Vendor-Class Option 60, length 8: "MSFT
5.0"<BR>
Parameter-Request Option 55, length
12:<BR>
Subnet-Mask, Domain-Name, Default-Gateway,
Domain-Name-Server<BR>
Netbios-Name-Server, Netbios-Node, Netbios-Scope,
Router-Discovery<BR>
Static-Route, Classless-Static-Route, Classless-Static-Route-Microsoft,
Vendor-Option<BR>
Agent-Information Option 82, length
14:<BR>
Unknown SubOption 2, length
6:<BR>
0x0000: 0013 71e7
68ee<BR>
Unknown SubOption 43, length
4:<BR>
0x0000: ac12 03f5<BR>14:29:21.017506 IP (tos 0x0, ttl 64, id 0, offset 0,
flags [DF], proto UDP (17), length 335) 123.123.224.42.67 > 123.123.230.1.67:
BOOTP/DHCP, Reply, length 307, hops 1, xid 0x39e50835, Flags
[none]<BR> Your-IP
123.123.233.232<BR>
Server-IP
123.123.224.42<BR>
Gateway-IP
123.123.230.1<BR>
Client-Ethernet-Address
00:19:99:a0:51:13<BR>
Vendor-rfc1048
Extensions<BR>
Magic Cookie
0x63825363<BR>
DHCP-Message Option 53, length 1:
ACK<BR>
Server-ID Option 54, length 4:
123.123.224.42<BR>
Lease-Time Option 51, length 4:
600<BR>
Subnet-Mask Option 1, length 4:
255.255.255.0<BR>
Domain-Name Option 15, length 11:
"sweden.se"<BR>
Default-Gateway Option 3, length 4:
123.123.235.1<BR>
Domain-Name-Server Option 6, length 8:
213.50.29.170,208.67.222.222<BR>
Agent-Information Option 82, length
14:<BR>
Unknown SubOption 2, length
6:<BR>
0x0000: 0013 71e7
68ee<BR>
Unknown SubOption 43, length
4:<BR>
0x0000: ac12 03f5<BR></FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2 face=Arial>Any help is much
appreciated!</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial>/Fredrik</FONT></SPAN></DIV>
<DIV><SPAN class=824125613-08092011><FONT size=2
face=Arial> </DIV></FONT></SPAN></BODY></HTML>