IP Routing
By Ravi Malhotra
This errata page lists errors outstanding in the most recent printing.
If you have technical questions or error reports, you can send them to
booktech@oreilly.com. Please specify the printing date of your copy.
This page was updated September 17, 2002.
Here's a key to the markup:
[page-number]: serious technical mistake
{page-number}: minor technical mistake
<page-number>: important language/formatting problem
(page-number): language change or minor formatting problem
?page-number?: reader question or request for clarification
Confirmed errors:
{4} R2's ip address is incomplete in figure
1-3. The address should be 1.1.1.3.
{4}
Code block in second half of page.
Change:
ip route 146.1.0.0 255.255.0.0 interface Ethernet0
To:
ip route 146.1.0.0 255.255.0.0 Ethernet0
(5) 2nd paragraph;
Change
"In the example in Figure 1-3, when the path R3 - R4
is added to the network it can be automatically
discovered by a routing protocol, such as ..."
To
"In the example in Figure 1-3, if a new path is added
between networks 1.0.0.0/8 and 146.1.0.0/16, it can be
automatically discovered by a routing protocol, such
as ..."
{8}
Table 1-1.
Add the following entries to the table :
EIGRP Summary Route 5
Internal E-IGRP 90
External EIGRP respectively 170
{12} 3rd item. last line. Change "received on
Ethernet 0" to "received on Ethernet 1".
{14} in the example of Ames, the last two lines.
"C 171.16.250.0 is directly connected, Serial0"
"C 171.16.252.0 is directly connected, Serial1"
should be
"C 171.16.252.0 is directly connected, Serial0"
"C 171.16.251.0 is directly connected, Serial1"
(14) 2nd paragraph. last line (singluar to plural
change).
change
"the routing table would look like this:"
to
"the routing tables would look like this:"
(18) 2nd paragraph, the last sentence.
"As an example, in line 1" should be
"As an example, in line 2".
{19} 12th line;
"Packet switching is very cpu intensive"
should be changed to
"Process switching is very cpu intensive"
(19) in the Section "Fast Switching", in the
second paragraph in this section.
change
"that matches the routing entry 204.148.185.192"
to
"that matches the routing entry 172.16.252.0"
(20)
about ten lines from the bottom of the page.
Change:
"further later in this section."
to
"later in this Section."
[21]
Figure 2-3.
Several changes in this diagram.
On routers A, B and C change all interfaces from
Ethernet to Serial:
On router A change E1 and E2 to S0 and S1,
respectively.
On router B change E1 and E2 to S0 and S1,
respectively.
On router C change E1 and E2 to S0 and S1,
respectively.
Along with the above change, drop the Ethernet
segments between the routers and replace with
point-to-point lines. After the change the diagram
will look very similar to Figure 2-1. However, we do
not need to show the link speed (56 kbps, T-1, T-1) in
Figure 2-3.
{21}
The first line on page 21 (in the code block under figure 2-3) reads:
C 172.17.1.9 is directly connected, Ethernet0
This line should be changed to:
C 172.17.1.0 is directly connected, Ethernet0
{21}
The last line in the first paragraph under the top code block currently reads:
At the moment this routing table snapshot was taken, A's invalid timer for 172.16.50.0 and B's update timer for 172.16.50.0 would both be 11 seconds.
This line should be changed to:
At the moment this routing table snapshot was taken, A's invalid timer for 172.17.50.0 and B's update timer for 172.17.50.0 would both be 11 seconds.
{21}
The second code block at the bottom of page 21 currently goes as follows:
A>sh ip route
C 192.168.1.0 is directly connected, Ethernet1
172.17.0.0/16 is subnetted, 6 subnets
C 172.17.1.9 is directly connected, Ethernet0
C 172.17.250.0 is directly connected, Serial0
C 172.17.251.0 is directly connected, Serial1
R 172.17.50.0 [120/1] via 172.17.250.2, 0:00:41, Serial0
R 172.17.100.0 [120/1] via 172.17.251.2, 0:00:19, Serial1
R 172.17.252.0 [120/1] via 172.17.250.2, 0:00:41, Serial0
[120/1] via 172.17.251.2, 0:00:19, Serial1
This code block should be changed to:
A>sh ip route
C 192.168.1.0 is directly connected, Ethernet1
172.17.0.0/16 is subnetted, 6 subnets
C 172.17.1.0 is directly connected, Ethernet0
C 172.17.250.0 is directly connected, Ethernet1
C 172.17.251.0 is directly connected, Ethernet2
R 172.17.50.0 [120/1] via 172.17.250.2, 0:00:41, Ethernet1
R 172.17.100.0 [120/1] via 172.17.251.2, 0:00:19, Ethernet2
R 172.17.252.0 [120/1] via 172.17.250.2, 0:00:41, Ethernet1
[120/1] via 172.17.251.2, 0:00:19, Ethernet2
{21}
fourth line from the bottom of the page.
Change:
The invalid timer for 172.16.50.0 is now at 41
seconds.
To:
The invalid timer for 172.17.50.0 is now at 41
seconds.
{22} 3rd line from the top, at
the end of that line, 'about 172.16.0.0' should be
'about 172.16.50.0'.
{24}
Change figure title:
Figure 2-6. Counting to infinity.
To:
Figure 2-6. Counting to infinity. Each diagram shows
relevant routing table entries for network X. As an
example, in diagram 1, router B knows that X is 1 hop
away in the direction of A, and router C knows that X
is 2 hops away in the direction of B. The direction of
each arrow should not be confused with the direction
of RIP updates.
{27}, the last sentence in the last paragraph
should be changed as follows
"As I stated earlier, since Phoenix" to
"As I stated earlier, since SantaFe"
{29} the command output at the top, the last line
"R 0.0.0.0 [120/1] via 192.199.1.34, ..." should be
"R 0.0.0.0 [120/1] via 192.100.1.34, ..."
{29}
Section "Routes to hosts";
Delete Reference to figure 2-8 in the first line. In other words,
Change:
in "quiet" or "silent" mode (Figure 2-8).
To:
in "quiet" or "silent" mode.
{30}
Figure 2-8.
Under router SantaFe add an Ethernet segment with the IP address 192.100.1.32/28.
Also, change title of figure to "Route Summarization."
{31}
In the code block in the first half of the page, about 15 lines down from the top:
Change:
R 172.16.1.0 [120/2] via 172.16.251.1, 0:00:09, Serial1
To:
R 172.16.1.0 [120/2] via 172.16.252.1, 0:00:21, Serial0
{35}
enumeration no.3 (starting with 'By exclusion'),
last line,
"received on Ethernet0" should be
"received on Ethernet1".
{39} lines 2-3. The word 'delay' appears twice.
Change:
"IGRP converts bandwidth, delay, reliability, delay,
and MTU..."
to
"IGRP converts bandwidth, delay, reliability and
MTU..."
{39}
4th or 5th line from the bottom of the page.
Change
with a delay of 1,000 ms.
To
with a delay of 1,000 usec.
{40} This change applies to pages 40 and 113. On both
pages, there are tables with notes at the end of each
table. Both notes (pages 40 and 113) should be changed
as follows:
Change
All serial interfaces on Cisco routers are configured
with the same default bandwidth (1,544 kbits/s) and
delay (20,000 ms) parameters.
To
All synchronous serial interfaces on Cisco routers are
configured with the same default bandwidth (1,544
kbits/s) and delay (20,000 us) parameters.
{41}
About the 8th line down :
Change
a delay of 10,000 ms.
To
a delay of 10,000 usec or 10 ms.
{44}
About the middle of the page
Change
BandW + Delay = 1,000 + 2,100 = 3,100
To:
BandW + Delay = 6,476 + 2,100 = 8,576
(44) Footnote
Replace the footnote on this page with the following text:
The concept of an outgoing interface is best
illustrated with an example. In TraderMary's network,
the outgoing interfaces from NewYork to 172.16.100.0
(on the path via Chicago) are NewYork interface
Serial0, Chicago interface Serial1, and Ames interface
Ethernet0. When computing the metric from NewYork to
172.160.0.0 on this path, we will use the IGRP
parameters of bandwidth, delay, load, reliability and
MTU for these interfaces. We will not use the IGRP
parameters from the opposite end of these same links:
in other words, we will not use the IGRP parameters
from Chicago interface Serial0 and Ames interface
Serial0. However, unless they have been asymmetrically
modified, the IGRP parameters on this second set of
interfaces would be identical to the first.
{45} in the description of path 2, equation
BandW = 10,000,000/56 = 6,476 should be
BandW = 10,000,000/1,544 = 6,476
{47} in the last sentence in the first paragraph.
Change:
"Why is it that NewYork and Ames did not pick up
the lower bandwidth for the 56kbps link?"
To:
"Why did NewYork and Ames not pick the higher
bandwidth (T-1) path via Chicago?"
{60} 1st paragraph, right after the subsection title
(Classful Route Lookups).
Change
"(see line 7 in the previous code block)"
To
"(via the no ip classless command)"
{61} The code block in the lower middle part of the
page
branch1# ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1,
timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip
min/avg/max = 40/50/80 ms
should be replaced with the following code block:
branch1# ping 172.16.10.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.10.1,
timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
{66} 6th line from the top.
"Ethernet0" should be "Ethernet1".
{72} 1st paragraph, 5 lines down.
Change
...is 2,707,456 (BandW = 1,544 and Delay = 4,100)
To
...is 2,707,456 (BandW = 6,476 and Delay = 4,100).
{75} Figure 4-4.
The update from Ames to NewYork is labelled
{destination: 172.16.500.0 cost: 2,195,456}.
This label should be changed to:
{destination: 172.16.50.0 cost: 2,195,456}.
{81} 3 or 4 lines from the bottom of the page:
Change:
"X is redistributing routes from RIP to IGRP"
To
"X is redistributing routes from RIP to EIGRP"
{83}
There are three changes in the long code block on this page:
First, change
interface Serial1
description Chicago to Ames link
ip address 172.16.250.9 255.255.255.0
To
interface Serial1
description Chicago to Ames link
ip address 172.16.250.9 255.255.255.252
----------
Second, change:
interface Serial0
description Ames to Chicago link
ip address 172.16.250.10 255.255.255.0
To
interface Serial0
description Ames to Chicago link
ip address 172.16.250.10 255.255.255.252
-----------------
Third, change:
interface Serial1
description Ames to New York link
bandwidth 56
ip address 172.16.250.6 255.255.255.0
To
interface Serial1
description Ames to New York link
bandwidth 56
ip address 172.16.250.6 255.255.255.252
{84} Figure 4-9.
The labels on the routers "NewYork" and "Chicago" need
to be reversed. After the correction is made "NewYork"
will have the direct link to "London" (and not
"Chicago").
{84} 2nd paragraph, 4th line, first word.
IGRP should be changed to EIGRP.
(85) figure 4-10.
There is a typographic error in the figure. There are
three networks under router "Shannon" labelled
172.16.100.0
172.16.101.0
172.16.102.0
The above numbers should be changed to
172.20.100.0
172.20.101.0
172.20.102.0
(88) The six lines just above the section labelled
"Default Routes" should read as follows:
Ames could now be configured to summarize its block
using the statement on its serial interfaces:
ip summary-address eigrp 10 172.16.96.0 255.255.240.0
and Chicago could be configured to summarize its block
using the statement on its serial interfaces:
ip summary-address eigrp 10 172.16.48.0 255.255.240.0
{90} two lines below the code block in the bottom
middle of the page...
"... A, B, and C share an Ethernet segment and run
EIGRP 10, all four routers should..."
the above should be changed to
"... A, B, and C share an Ethernet segment and run
EIGRP 10, all three routers should..."
{95} Seventh line from the bottom of the page.
Change
Let's now take one of these subnets (say,
172.15.250.0)...
To
Let's now take one of these subnets (say, 172.16.250.0)...
{97}
There are three changes in the long code block on this page:
First, change
interface Serial1
description Chicago to Ames link
ip address 172.16.250.9 255.255.255.0
To
interface Serial1
description Chicago to Ames link
ip address 172.16.250.9 255.255.255.252
---------------
Second, change:
interface Serial0
description Ames to Chicago link
ip address 172.16.250.10 255.255.255.0
To
interface Serial0
description Ames to Chicago link
ip address 172.16.250.10 255.255.255.252
---------------
Third, change:
interface Serial1
description Ames to New York link
bandwidth 56
ip address 172.16.250.6 255.255.255.0
To
interface Serial1
description Ames to New York link
bandwidth 56
ip address 172.16.250.6 255.255.255.252
{104 and 105}
There are several instances of the expression "1782
feet" on these pages. All these instances should be
change to "1782feet" -- note we are deleting the space
between "1782" and "feet."
This expression occurs on page 104 at the following
places:
1. end of second paragraph.
2. in first code block.
3. in second code block.
4. in the middle paragraph on the page.
This expression occurs on page 105 at the following
places:
1. in first code block.
2. in the middle paragraph on the page.
{113} 3 lines down below the code block.
Change
"mask information (24 bits, or 255.255.255.0)"
To
"mask information (16 bits, or 255.255.0.0)"
Thanks to Susumu for catching another error.
{113}
The footnote below Table 6-1 should be changed as
follows:
Change
All serial interfaces on Cisco routers are configured
with the same default bandwidth (1,544 kbits/s) and
delay (20,000 ms) parameters.
To
All synchronous serial interfaces on Cisco routers are
configured with the same default bandwidth (1,544
kbits/s) and delay (20 ms) parameters.
(127)
There is a spelling error on the 15th line from the
top: "elegible" should be changed to "eligible."
{128}
In the code block, at line 14:
"Adjacent with neighbor 69.1.1.1" should be
"Adjacent with neighbor 172.16.252.1"
(139) first code block on the page.
The last line in this first code block is numbered 44
(the line reads "O 172.16.100.0 [110/192] via...").
The line number (44) should be moved to the first line
in the code block (the line reading "O IA 10.0.0.0/8
[110/1795] via...").
{139}
In the middle of the page in the section "Summarizing
at the ASBR (or External Route Summarization)"
Change:
"Note from the figure that the RIP network contains
routes in the network 10.3.0.0/24 (the RIP subnets may
be 10.3.1.0/24, 10.3.2.0/24, 10.3.3.0/24,
...10.3.255.0/24). It is desirable to summarize
10.3.0.0/16 into the OSPF network rather than carrying
the individual subnets."
to
"In this configuration let network 10.0.3.0/24 contain
other routers running RIP and sending updates to
router Paris (the RIP subnets may be 10.0.3.0/26,
10.0.3.64/26,
10.0.3.128/26 and 10.0.3.192/26). It is desirable to
summarize 10.0.3.0/24 into the OSPF network rather
than carrying the individual subnets "
(139)
last line on page
change
"summary-address 10.3.0.0 255.255.252.0"
to
"summary-address 10.0.3.0 255.255.255.0".
(140)
Fifth or sixth line down from the top.
change
"The LS database will now contain a single external
LSA with link state ID of 10.3.0.0 advertised by
Paris."
to
"The LS database will now contain a single external
LSA with link state ID of 10.0.3.0 advertised by
Paris."
[142]
Change on the first line on the page:
Change:
specifies the ABR with which
To
specifies the OSPF Router ID of the ABR with which
Change in the second paragraph:
Change:
Remember that a virtual link can be created only between ABRs and can traverse only one area.
To:
Remember that a virtual link can be created only between OSPF Router IDs of ABRs, and can traverse only one area.
(154) Section "Route Summarization"
Please replace the four lines in this section with the
following text:
If an area has multiple ABRs and one ABR announces
more specific routes than the others, the traffic will
follow the more specific routes. If you observe that
one ABR is doing all the work but the others are
relatively idle, check the route summarization
statements. If you intend to use all ABRs equally, all
ABRs must have identical summary statements.
{155}
4th line after the code block,
Change
"set to 10 seconds (line 61)."
To
"set to 10 seconds (line 62)."
(161)
There are several typos in the last paragraph on page
161. I would like to replace the text in the last
paragraph with new text.
Replace the following paragraph:
"Multi-homing to different ISPs also creates problems
with this schema. Uncle-Q has the address block
180.180.1.0/24 from ISP-X but he also connects to
ISP-Z. ISP-Z would have to carry Brother-X's specific
route 180.180.1.0/24. In other words, since ISP-Z
advertises Brother-X's prefix, the routing tables in
the attached ASs would see both the aggregate
180.180.0.0/16 from ISP-X and 180.180.1.0 from ISP-A.
However, addresses may still be aggregated at a higher
level in the network, based on address hierarchy."
With the following paragraph:
"Multi-homing to different ISPs also creates problems
with this schema. Uncle-Q has the address block
180.180.2.0/24 from ISP-X but let's say that Uncle-Q
also establishes a connection to ISP-Z. ISP-Z would
have to carry Uncle-Q's specific route 180.180.2.0/24.
In other words, since ISP-Z advertises Uncle-Q's
prefix, the routing tables in the attached ASs would
see both the aggregate 180.180.0.0/16 from ISP-X and
180.180.2.0 from ISP-Z. However, addresses may still
be aggregated at a higher level in the network, based
on address hierarchy."
(163); top line.
Change
"...TraderMary uses the registered Class C
addresses..."
To
"...TraderMary uses the registered addresses..."
{164}
Figure 7-3 has a typo in AS 100 (TraderMary). the
address 192.200.2AA.1 should be changed to
192.200.200.1.
{174}
in the middle of the page.
Change:
"When the network statement is used to advertise a
prefix, the ORIGIN attribute for the route is set to
IGP."
To:
"When the network statement is used to advertise a
prefix, the ORIGIN attribute for the route is set to
IGP, which is represented by the symbol 'i' in the BGP
Table."
(175)
second paragraph.
Change:
"When an IGP is redistributed into BGP, the ORIGIN
attribute is set to "?"."
To:
"When an IGP is redistributed into BGP, the ORIGIN
attribute is set to Incomplete which is represented by
the symbol "?" in the BGP Table."
{178} line 2
Change
"The default value of the attribute is "?"."
To
"The default value of the attribute is 100."
(184) Figure 7-8;
There is a line with an arrow between Router X and Router A saying "I-BGP." Change "I-BGP" to "E-BGP."
{192}
line 48 in the code block:
Change
"neighbor 99.0.0.1 update-source loopback0"
to
"neighbor 98.2.0.1 update-source loopback0"
line 49 in the code block:
Change
"neighbor 99.0.0.1 ebgp-multihop"
to
"neighbor 98.2.0.1 ebgp-multihop"
{197}
Change lines 57 and 58
from
neighbor 192.100.100.253 remote-as 109
neighbor 192.100.100.253 route-map metric-adj2 out
To
neighbor 146.100.100.253 remote-as 109
neighbor 146.100.100.253 route-map metric-adj2 out
(197)
Changes lines 67 and 68 from
neighbor 200.1.1.253 remote-as 109
neighbor 200.1.1.253 route-map metric-adj out
To:
neighbor 146.1.1.253 remote-as 109
neighbor 146.1.1.253 route-map metric-adj out
(198)
middle of page.
Line number 71 is attached to the following line:
* 192.100.1.0 146.1.1.254 0 209 209 209 i
Instead of the above line, line number 71 should be
attached to the line immediately below, which reads:
*> 146.100.100.254 0 0 209 i
The new line 71 should be in bold and the old line 71
should not be in bold. Nothing else changes in the
code block.
{198} line 73 and 74 in the code block in the middle
of the page.
line 73 should read
"B 192.100.1.0/24 [20/0] via 146.100.100.254, ..."
and line 74 should read
"192.100.2.0/24 [20/0] via 146.1.1.254, ..."
(198) last line on page (in code block)
Change:
Gateway of last resort is 192.100.100.253 to network
To:
Gateway of last resort is 146.100.100.253 to network
0.0.0.0
(199)
first line on page, (numbered 75).
Change
"...[20/0] via 192.100.100.253, 00:07:21"
To
"...[20/0] via 146.100.100.253, 00:07:21"
(199) third line down..
In the code block that begins "Madras#sh ip route."
Change
"Gateway of last resort is 200.1.1.253 to network
0.0.0.0"
To
"Gateway of last resort is 146.1.1.253 to network
0.0.0.0"
(199)
Line number 76 in the code block...
Change
"B* 0.0.0.0/0 [20/0] via 200.1.1.253, 00:04:47"
To
"B* 0.0.0.0/0 [20/0] via 146.1.1.253, 00:04:47"
Also, please make this line (line number 76) bold.
(199),
Line 77 in the code block...
Change
"*> 0.0.0.0 192.100.100.253 0 0 109 ?"
To
"*> 0.0.0.0 146.100.100.253 0 0 109 ?"
(199),
The line just below line 77 in the code block...
Change
"* i 200.1.1.253 0 100 0 109 ?"
To
"* i 146.1.1.253 0 100 0 109 ?"
(199),
Line 78 in the code block...
Change
"*> 0.0.0.0 200.1.1.253 0 0 109 ?"
To
"*> 0.0.0.0 146.1.1.253 0 0 109 ?"
(199),
The line just below line 78 in the code block...
Change
"* i 192.100.100.253 0 100 0 109 ?"
To
"* i 146.100.100.253 0 100 0 109 ?"
[205] Middle of page;
Change
distribute-list 1 out interface Ethernet1
To
distribute-list 1 out Ethernet1
-------------------------------
I brought this second copy of the book hoping the errors were fixed in the second edition but the book shipped to me was first edition.
Is there a way I can get the PDF format of the books if the error fixed.
Thanks,
Mukhtar