cfsalmeida
IS-IT--Management
In General, IP routing on Solaris is strictly destination based and Solaris does not necessarily respond back out on the same interface as the input packet arrived. Solaris uses standard IP routing, and will respond back out on first match in the routing table. As of Solaris 8 Update 2, there is a change in source address selection. Solaris 8 uses the inbound packet destination address as the source address of the outbound packet. This means that packets that come in on a certain IP address now leaves with that as its source address and not the "primary" physical address interface as in previous releases of Solaris.
IP outgoing interface selection behavior depends on whether ip_enable_group_ifs is on or off. With the latest IP module, ifgrps is off by default.
Check using the ndd command:
ndd /dev/ip ip_enable_groups_ifs
Interface Groups (ifgrps), can be used to do load balancing, in Solaris 2.6, in S8 is used IPMP (IP multipathing)
Without S8 or Interface Groups, and with multiple interfaces having the same network route, the outgoing interface selected is the one that comes first in the logical order (check with " route get IP# " , and " netstat -rvan "
. The primary (lowest interface instance) is usually selected as the first interface in the routing list that corresponds to that subnet. The startup boot scripts configure the interfaces alpha-numerically as they appear in the S72inetsvc startup script: hme0 first, hme1 second, hme1:1 third, le0 so forth.
"ifconfig'ing" interfaces manually (after S72inetsvc) may cause the previous interface to be first in the routing table, which may not be as expected. Re-applying ifconfig to all interfaces will re-sort it back in the right order
(the default, the outgoing interface will be the one that comes first in the logical order in the routing table). Use the command from /etc/rc2.d/S72inetsvc), i.e.
" ifconfig -auD netmask + broadcast + "
Depending on the configuration, unwanted duplicate network routes can be removed with
" route delete {interface-IP#} {subnet#} "
Solaris 8 has added a deprecated option to the ifconfig command to control this
" ifconfig qfe1 {interface-IP#} deprecated "
IP outgoing interface selection behavior depends on whether ip_enable_group_ifs is on or off. With the latest IP module, ifgrps is off by default.
Check using the ndd command:
ndd /dev/ip ip_enable_groups_ifs
Interface Groups (ifgrps), can be used to do load balancing, in Solaris 2.6, in S8 is used IPMP (IP multipathing)
Without S8 or Interface Groups, and with multiple interfaces having the same network route, the outgoing interface selected is the one that comes first in the logical order (check with " route get IP# " , and " netstat -rvan "
. The primary (lowest interface instance) is usually selected as the first interface in the routing list that corresponds to that subnet. The startup boot scripts configure the interfaces alpha-numerically as they appear in the S72inetsvc startup script: hme0 first, hme1 second, hme1:1 third, le0 so forth."ifconfig'ing" interfaces manually (after S72inetsvc) may cause the previous interface to be first in the routing table, which may not be as expected. Re-applying ifconfig to all interfaces will re-sort it back in the right order
(the default, the outgoing interface will be the one that comes first in the logical order in the routing table). Use the command from /etc/rc2.d/S72inetsvc), i.e.
" ifconfig -auD netmask + broadcast + "
Depending on the configuration, unwanted duplicate network routes can be removed with
" route delete {interface-IP#} {subnet#} "
Solaris 8 has added a deprecated option to the ifconfig command to control this
" ifconfig qfe1 {interface-IP#} deprecated "