dladm is the admin utility for Data-Link Interface which helps to display informarthe like Link Status (UP/DOWN), Speed, Duplex, MTU, VLAN Tagged and crucially statistics of network traffic on each of the interfaces historically as well as in real time. dladm can also configure and admin Link Aggregation on multiple NICs which we will not focus here.

Show Link Status/Speed/Duplex

# dladm show-dev
nxge0           link: down      speed: 0     Mbps       duplex: unknown
nxge1           link: down      speed: 0     Mbps       duplex: unknown
nxge2           link: up        speed: 1000  Mbps       duplex: full
nxge3           link: up        speed: 1000  Mbps       duplex: full

As you can see above the “show-dev” option lists all the network interfaces with Link Status (UP/DOWN), current speed in Mbps and Duplex (Half/Full)

Show Link Status

# dladm show-link
nxge0           type: non-vlan  mtu: 1500       device: nxge0
nxge1           type: non-vlan  mtu: 1500       device: nxge1
nxge2           type: non-vlan  mtu: 1500       device: nxge2
nxge3           type: non-vlan  mtu: 1500       device: nxge3

Here “show-link” option reveals the MTU and the VLAN tagging detail on each of the interfaces on the system.

Show Stats of all Interfaces for all time

# dladm show-dev -s
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge0           0         0           0       0         0           0
nxge1           0         0           0       0         0           0
nxge2           179625752557169463759657      581104982 3964684165410
nxge3           22240891  1834257868  0       5198483   395084708   0

The “-s” option along with “show-dev” or “show-link” displays network traffic statistics including Input/Output packets, input/output errors.

Stats in real-time

To show the stats of a particular interface in real-time use the “-i” option which is the interval in seconds. The first line shows again historic stats and later on the real-time information for every “n” seconds (5 seconds in our example)

# dladm show-link -s -i 5 nxge2
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge2           179637824757173944575957      581119516 3964706801670
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge2           961       319105             0       150       17874       0
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge2           887       263850             0       117       16505       0

If we fail to mention the interface then it takes the default interface (1st in the list). As you can see from the example below, we see stats for nxge0 which is not connected.

# dladm show-link -s -i 5
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge0           0         0           0       0         0           0
ipackets  rbytes         ierrors opackets        obytes      oerrors
nxge0           0         0           0       0         0           0

The PCP script works on Solaris 10/9/8 and can be downloaded from here. Simply save the pcp.txt file to your Solaris Server as a Shell scripts (say pcp.sh) and change permissions to execute.

# chmod 755 pcp.sh

PIDs for TCP Port

Run PCP with “-p” option to show the PIDs of processes having a TCP port (say Port 22)

For instance, to find PIDs opening TCP port 22.

TCP Ports open by PIDs

Run PCP with “-P” option to show the TCP ports open by specific PID

For instance, here I try to find the TCP ports open by PID 18805

All PIDs for all open TCP Ports

Use the “-a” option to list all TCP ports open with all the PIDs

Ensure that every interface that is up and connects to a network has a file /etc/hostname.interface file created say /etc/hostname.pcn0 where pcn0 is my network interface. If they are not found the create a file as follows:

solaris10# touch /etc/hostname.pcn0

where pcn0 is my network interface card. 

dhcpagent is the dhcp client thats running on your Solaris operating system. With this in place create the following file:

Create /etc/dhcp.<interface>

Similarly, create a /etc/dhcp.<interface> file (here /etc/hostname.pcn0)

solaris10# touch /etc/dhcp.pcn0

Again, if there are more than one network interface and if each of these receive IP Address from DHCP servers in their networks then a /etc/dhcp.<interface> file has to be created for each of these interfaces.

The system by default waits for 30 seconds for the DHCP Server to respond. However, this can be modified by entering the wait time in the dhcp.<interface> file. For instance, if I decide to let my solaris server wait for 90 seconds  then enter the wait time as follows

solaris10# cat /etc/dhcp.pcn0
wait 90

If it is a primary interface then this can be mentioned as follows

solaris10# cat /etc/dhcp.pcn0
wait 90
primary

This should make your Sun Solaris Server a DHCP client to receive IP Address from a DHCP Server. For more customisation options click here

If you did a “netstat -r”

sunsolaris# netstat -r

Routing Table: IPv4
  Destination           Gateway           Flags  Ref   Use   Interface
——————– ——————– —– —– —— ———
BASE-ADDRESS.MCAST.NET solaris10            U         1      0 hme0
default              192.168.0.1          UG        1      0 hme0
localhost            localhost            UH        1     61 lo0

You may not find that the network for the Network interface not found in there (192.168.0.0 here) and as you would expect adding the netmask manually fixes the problem.

sunsolaris# ifconfig hme0 255.255.0.0

The problem with not being able to bring an interface up at a reboot indicates a problem with the /etc/hostname.interface file (here /etc/hostname.hme0). It could be with an extra line in your hostname.interface file (here hostname.hme0) that causes the problem with the interface.

To check if thats the problem,

sunsolaris# wc /etc/hostname.hme0
                  2       0       2 /etc/hostname.hme0

It should report as “1″ line and not as “2″ as above. To fix the problem from occuring again,, edit the hostname.interface file and delete the extra file.

sunsolaris# vi /etc/hostname.hme0

and delete the extra empty line in the bottom and that should fix the problem.

The default time for which a dynamically learnt Route entry in the routing table is 20mins (1200000ms)

To Display current Route holding time

To display the current time interval to hold a route entry

In Solaris 8/9/10

sunsolaris# ndd -get /dev/ip ip_ire_arp_interval
1200000

In earlier versions to Solaris 8

sunsolaris# ndd -get /dev/ip ip_ire_flush_interval

To modify the Route holding time 

This can be modified or reduced to a lower level. To modify the default time to say 15 mins

In Solaris 8/9/10

sunsolaris# ndd -set /dev/ip ip_ire_arp_interval 900000

In earlier versions to Solaris 8

sunsolaris# ndd -set /dev/ip ip_ire_flush_interval 900000

Display ARP table

sunsolaris# arp -a
Net to Media Table: IPv4
Device   IP Address               Mask      Flags   Phys Addr
—— ——————– ————— —– —————
pcn0   192.168.0.1          255.255.255.255       00:18:4d:f8:a4:6e
pcn0   192.168.0.2          255.255.255.255       00:13:ce:85:0e:e1
pcn0   sunsolaris            255.255.255.255 SP    00:0c:29:d3:76:89
pcn0   BASE-ADDRESS.MCAST.NET 240.0.0.0       SM    01:00:5e:00:00:00

Delete an ARP entry

sunsolaris# arp -d 192.168.0.1
192.168.0.1 (192.168.0.1) deleted

To verify the entry indeed is deleted

sunsolaris# arp -a
Net to Media Table: IPv4
Device   IP Address               Mask      Flags   Phys Addr
—— ——————– ————— —– —————
pcn0   192.168.0.2          255.255.255.255       00:13:ce:85:0e:e1
pcn0   solaris10            255.255.255.255 SP    00:0c:29:d3:76:89
pcn0   BASE-ADDRESS.MCAST.NET 240.0.0.0       SM    01:00:5e:00:00:00

You can see the ARP entry for 192.168.0.1 is longer found.

Add a Static entry

sunsolaris# arp -s 192.168.0.1 00:18:4d:f8:a4:6e

Syntax is

arp -s HOSTNAME MAC-Address <pub/temp/trail>

where

pub – publishes the ARP entries to other hosts on the network

temp – Temporary entry

trail – Allows Trailer Encapsulations to be sent to host

You can also read static entries from a file. This can come handy if you decide that all ARP entries are static and no ARP requests are sent and received from the system. You can add the static entries onto a file and add the arp command onto the network init scripts in /etc/rc2.d/

To read from file

sunsolaris# arp -f /etc/host_mac

where /etc/host_mac is my file name from where the ARP entries are read.

To check the current ARP caching time

sunsolaris# ndd -get /dev/arp arp_cleanup_interval
500000

where 500000 in milliseconds indicates 5mins

To modify ARP Cache timing, click here

The default time that ARP entries are cached in a Sun Solaris system is 5 mins.

However, this can be reduced to lower level (say 3mins). This means that the number of ARP requests and ARP replies to and from the server will increase as a result. So, before modifying the caching time, check if this can cause andy congestion on your network.

To set the ARP cache time period

solaris# ndd -set /dev/arp arp_cleanup_interval 180000

The above command sets the interval to 3 minutes (1min is equal to 60000ms). Now, all the ARP entries are flushed at a faster rate (every 3mins)

For this change to persist across reboots, add this command onto the init scripts in /etc/rc2.d directory for your network interface (where all the required ndd commands are run).

In Solaris 10, IP Forwarding can be enabled or disabled using the routeadm & ifconfig commands as against the ndd commands in Solaris 9 and earlier. The advantage is the change dynamic and real-time and the change persist across reboot unlike the ndd command.

Enable/Disable IP Forwarding globally 

To globally enable IP Forwarding in Solaris 10 use the routeadm command as follows:

In IPv4

solaris10# routeadm -e ipv4-forwarding

In IPv6

solaris10# routeadm -e ipv6-forwarding

The switches “-e” enables IP Forwarding.

To disable IP Forwarding

In IPv4

solaris10# routeadm -d ipv4-forwarding

In IPv6

solaris10# routeadm -d ipv6-forwarding

The switches “-d” enables IP Forwarding.

After the change run the following command for the changes to take effect.

solaris10# routeadm -u

Enable/Disable IP Forwarding per interface 

To enable IP Forwarding on a specific interface (say ce0) using the ifconfig command

In IPv4

solaris10# ifconfig ce0 router

In IPv6

solaris10# ifconfig ce0 inet6 router

To disable IP Forwarding for an interface (say ce0)

In IPv4

solaris10# ifconfig ce0 -router

In IPv6

solaris10# ifconfig ce0 inet6 -router

The DHCP Agent by default requests for the

Subnet Mask

Default Router

Hostname

DNS Domain

Broadcast Address

Encapsulated Vendor Option (vendor specific information as described in RFC 2132)

The DHCP Agent config file is

/etc/default/dhcpagent

In the file look for the line

PARAM_REQUEST_LIST=1,3,6,12,15,28,43

This is the line that defines what is being requested for from the DHCP Server. Here, each number stands for one of the above mentioned parameters where

1 = subnet mask

3 = Default Router

6 = DNS Server

12 = hostname

15 = DNS Domain Name

28 = broadcast address

43 = Encapsulated Vendor options

If you decide to not request for any of the above parameters then all you need to do is to remove the corresponding number from the PARAM_REQUEST_LIST. Let’s say you do not want to request for the hostname then simply remove the number “3″ and the “,” that follows so it looks as follows

PARAM_REQUEST_LIST=1,6,12,15,28,43

Once done,save the file. The next time the system restarts the hostname is not requested for from the DHCP Server.