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IceWee — Fri, 12 Aug 2016 02:47:00 GMT

�q�个问题很多��伙伴都遇到了，�|�上搜罗了半天也没找到太好、太完美的解军_��法，有�h说是因�ؓ安装IE11时联�|�了�Q�导致自动打了补丁，�q�个补丁可以自动��查IE主页是否损坏�Q�可以通过卸蝲相应的补丁解冻I��我同时又扑ֈ�了另外一个通过修改hosts文�g的方法，貌似目前解决了我的问题，修改�Ҏ��如下�Q? 使用��C��本打开 C:\Windows\System32\drivers\etc\hosts 文�g�Q�在最下面�q�加一行： 127.0.0.1 ieonline.microsoft.com

IceWee 2016-08-12 10:47 发表评论

tomcat安装为服务service.bat讄��Q�启动服务时出错�Q�提�C��?..特定代码0�?

IceWee — Mon, 18 Jan 2016 05:43:00 GMT

��JDK中BIN文�g夹下�?msvcr71.dll �q�个文�g复制�?TOMCAT 中的 BIN �?img src ="http://www.aygfsteel.com/icewee/aggbug/429098.html" width = "1" height = "1" />

IceWee 2016-01-18 13:43 发表评论

ORA-01438: value larger than specified precision allowed for this column & Could not synchronize database state with session

IceWee — Fri, 28 Mar 2014 10:54:00 GMT

有段日子没做记录了，�q�段日子一直在排雷�Q�前人埋下的隐患代码�Q�或者直接说bug�Q�，今天�q�个雯��我排了将�q�大半天�Q�因为是正式上线的系�l�，只能看后台日志，不能调试�Q�打印出的异�怿�息不完整�Q�种�U�的条�g不充分，��D��问题很难定位。标题上的两个异常，�W�一个一看就明白是插入的数值大于数据库字段长度�Q�第二个多是因�ؓNumber�c�d��的字�D�导��_��比如�_�ֺ�不��?/span>

我们的这�ơ问题原因是�E�序员在做除法运��时没有寚w��数进行非零判断，��D��计算出来的数值非法，插入数据库失败，��L��代码�Q?

public static void main(String[] args) {
        double a = 10;
        double b = 0;
        double c = 0;

        double m = a/c;
        double n = b/c;

        System.out.println(m);
        System.out.println(n);
    }

�l�过计算后，m和n的值分别是多少�Q�没在实际开发中遇到的可能不知道�Q�或者你有个好习惯不会出现这��L��bug�Q�请看结果：

Infinity
NaN

被除数非�Ӟ��除数为零做除法的�l�果是字�W�串“Infinity”�Q�翻译成中文��是“无限”�Q�你的中学数学老师可能说过�Q?br />被除��Cؓ�Ӟ��除数为零做触发的�l�果是字�W�串“NaN”�Q�即不是有效的数字�?br />
��是�q�个“Infinity”��p��了我一��天的时间才定位。下面详�q�问题定位的�Ҏ��?br />
异常1�Q�ORA-01438: value larger than specified precision allowed for this column
了解�Ҏ��据库的打��g��看就知道插入的数��D��q�了表字�D�长度，但你知道是哪个表哪个字段吗？我不知道�Q�于是网上查阅了下，Oracle数据库服务器在Linux上�?br />
命��o行登陆到数据库所在服务器�Q�进入Oracle的安装目录，假设�?opt/oracle/
�q�入到如下目录：/opt/oracle/admin/实例�?udump
中间的数据库实例名根据实际情况修改，udump目录下会有一堆的.trc文�g�Q�这些文件记录了所有操作当前数据库出现异常的堆栈信息。�ؓ了定位问题，我将该目录下的所�?trc文�g都删除了�Q�当�Ӟ��删除之前把udump目录整个备䆾了）�Q�再�q�行一�ơ系�l�的业务操作�Q�查看一下udump目录�Q�发现立�ȝ��成一个新 �?trc文�g�Q�打开查看�Q�内容片�D�）�Q?br />

Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
ORACLE_HOME = /u01/app/oracle/product/10.2/db_1
System name:    AIX
Node name:    gsdj1
Release:    1
Version:    6
Machine:    00CFD4644C00
Instance name: bjwd1
Redo thread mounted by this instance: 1
Oracle process number: 132
Unix process pid: 48300280, image: oracle@gsdj1

*** SERVICE NAME:(bjwd) 2014-03-28 16:48:05.683
*** SESSION ID:(2969.43961) 2014-03-28 16:48:05.683
*** 2014-03-28 16:48:05.683
ksedmp: internal or fatal error
ORA-01438: value larger than specified precision allowed for this column
Current SQL statement for this session:
insert into CP_TEMP_STOCKTRAN (APPLY_ID, ALIEN, CER_TYPE, CER_NO, TRANS_AM, TRANS_AM_PR, TRANS_TYPE, TRANS_DATE, ENDORSOR, BLIC_TYPE, ALIEN_ID, ENDORSOR_ID, STOCKTRAN_ID) values (:1, :2, :3, :4, :5, :6, :7, :8, :9, :10, :11, :12, :13)

黄色背景�U�色字体的SQL��是�|�魁��R��Q�这仅仅能定位发生问题的数据库表�Q�字�D�还得自己排查。异�?让我定位��C��q�里�Q�这时想起了异常2�?br />

异常2�Q?nbsp;Could not synchronize database state with session
之前也搜索过�q�个异常�Q�多数是�׃��Number�c�d��的字�D�导致。冷静的思考一下，�q�_��我们在做表设计时�Q�会把文字类型的字段讄��大一些，Number�c�d��的精度也会根据实际业务进行设计，但往往Number�c�d��的字�D�|��Ҏ��出问题：
1、如果将非Number值插入该字段�Q�比如字�W�串
2、如果插入的数值精度过多，如字�D�设计Number(10,2)�Q�也��是最大支�?为整数和两位��数�Q�要插入34.121313��׃��p�|

�Ҏ��表名定位到hibernate的映��文件以及实体类�Q�再从业务功能入口（一个action�Ҏ��Q�搜索，�l�于定位��C��个业务接口做了该实体�cȝ��保存代码�Q�定位到了那个字�D�，定位��C��做除法没有判断除数是否�ؓ0�?br />

IceWee 2014-03-28 18:54 发表评论

Debian �|�络讄��以及非法��x��后无法联�|?connect: network is unreachable

IceWee — Fri, 24 Jan 2014 02:50:00 GMT

�|�络配置�Q?/span>
临时�Q�重�?/span>丢失�Q?/span>

ifconfig eth0 192.168.1.xxx netmask 255.255.xxx.0

�怹��Q�重启有效）

vi /etc/network/interfaces

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug eth0
iface eth0 inet static
        address 192.168.1.xxx
        netmask 255.255.xxx.0
        network 192.168.1.1
        broadcast 192.168.1.255
        gateway 192.168.1.1
        # dns-* options are implemented by the resolvconf package, if installed
        dns-nameservers 202.106.196.115

�׃��非法��x��D��重启后无法联�|?/span>

ifconfig eth0 192.168.1.xxx netmask 255.255.xxx.0

route add default gw 192.168.1.1

重启后配�|�丢失，所以必��d��重启之前执行�Q?br />

apt-get update

apt-get install ifupdown

不能联网是因为非法关机导致ifup脚本丢失

IceWee 2014-01-24 10:50 发表评论

SVN(Subversion)自动同步备䆾配置

IceWee — Thu, 23 Jan 2014 03:08:00 GMT

源机器：192.168.1.1
备䆾机器�Q?92.168.1.2

前提条�g�Q?br />1、两台机器的�|�络是连通的
2、两台机器必��d��时安装了SVN服务�?br />
假设�Q?br />源机器上需要同步的库名为autoSync�Q�访问地址为：svn://192.168.1.1/autoSync�Q�对其具备读写权限的账户�Q�sync/sync

备䆾机器配置�Q?br />1、创��Z��源机器库名相同的�I�库

# 假设备䆾机器的SVN根目录徏立在 /home/backup/svn/repository�?/span>
svnadmin create /home/backup/svn/repository/autoSync

2、配�|�备份机器上的autoSync
分别修改conf下的svnserve.conf、passwd、authz�Q�根据实际情况配�|�，假设创徏了用户sync/sync�Q�对库autoSync具备��d��权限�Q�配�|�方法略�Q�配�|�完成后启动SVN服务

3、创建�ƈ修改pre-revprop-change文�g

cd /home/backup/svn/repository/autoSync/hooks
cp pre-revprop-change.tmpl pre-revprop-change
vi pre-revprop-change

��文件末��?/span>�?#8220;exit 1”�?/span>改�ؓ“exit 0”卛_��Q�保存退�?br />

REPOS="$1"
REV="$2"
USER="$3"
PROPNAME="$4"
ACTION="$5"

if [ "$ACTION" = "M" -a "$PROPNAME" = "svn:log" ]; then exit 0; fi

echo "Changing revision properties other than svn:log is prohibited" >&2
exit 0

增加可执行权�?br />

chmod 755 pre-revprop-change

4、初始化
命��o�Q?br />svnsync init --username 用户�?--password 密码备䆾机器库URL 源机器库URL

说明�Q?br />用户名和密码是对源机器SVN库具备读写权限的SVN用户

�C�Z��Q?br />

svnsync init --username sync --password sync svn://192.168.1.2/autoSync svn://192.168.1.1/autoSync

5、首�ơ同�?br />首次同步即�ؓ一�ơ全备䆾�q�程�Q�在此期间请停止客户端段源机器哦一切操作（提交代码�{�）
命��o�Q?br />svnsync sync 备䆾机器库URL
�C�Z��Q?br />

svnsync sync svn://192.168.1.2/autoSync

源机器配�|?br />6、增量自动同步配�|?br />创徏�q�修改post-commit文�g

# 假设源机器的SVN根目录徏立在 /home/svn/repository�?/span>
cd /home/svn/repository/autoSync/hooks
cp post-commit.tmpl post-commit
vi post-commit

在文件末��追加：svnsync sync --non-interactive 备䆾机器库URL --username 用户�?--password 密码

说明�Q?br />用户名和密码是对备䆾机器SVN库具备读写权限的SVN用户

�C�Z��Q?br />

svnsync sync --non-interactive svn://192.168.1.2/autoSync --username sync --password sync

7、术�?br />配置完成�Q�今后客��L��再向SVN�Q?92.168.1.1�Q�提交文件时�Q�会自动触发源机器（192.168.1.1�Q�向备䆾机器�Q?92.168.1.2�Q�提交更�?br />
8、版本库UUID一致�?br />首先查看源机器库的UUID�Q�假讑־�到的是：fcdcbee9-6be3-4575-8d4a-681ec15ad8e0

svnlook uuid svn://192.168.1.1/autoSync

更新备䆾机器库的UUID为源机器库的UUID

svnadmin setuuid svn://192.168.1.2/autoSync fcdcbee9-6be3-4575-8d4a-681ec15ad8e0

IceWee 2014-01-23 11:08 发表评论

IceWee — Fri, 17 Jan 2014 07:48:00 GMT

本文记录的安装步骤是��Z��基本安装后的Debian�Q�启动后漆黑一片，只有命��o行，采用在线安装方式�Q�因此配�|�中国的镜像软�g源能提高软�g的下载速度�Q�首先配�|��Y件源�?/span>

备䆾源文�?/span>
# cp /etc/apt/sources.list /etc/apt/sources.list.bak

�~�辑源文�?/span>
# nano /etc/apt/sources.list

注释掉本地光盘源�q�一行，注释后如�Q?/span>
# deb cdrom:[Debian GNU/Linux 6.0.7 _Squeeze_ - Official amd64 NETINST Binary-1 20130223-18:50]/ squeeze main

取消下面两行官方源前面的注释
deb http://security.debian.org/ squeeze/updates main
deb-src http://security.debian.org/ squeeze/updates main

�q�加163的镜像源地址
deb http://mirrors.163.com/debian/ squeeze main non-free contrib
deb http://mirrors.163.com/debian/ squeeze-proposed-updates main contrib non-free
deb http://mirrors.163.com/debian-security/ squeeze/updates main contrib non-free
deb-src http://mirrors.163.com/debian/ squeeze main non-free contrib
deb-src http://mirrors.163.com/debian/ squeeze-proposed-updates main contrib non-free
deb-src http://mirrors.163.com/debian-security/ squeeze/updates main contrib non-free
deb http://ftp.sjtu.edu.cn/debian/ squeeze main non-free contrib
deb http://ftp.sjtu.edu.cn/debian/ squeeze-proposed-updates main contrib non-free
deb http://ftp.sjtu.edu.cn/debian-security/ squeeze/updates main contrib non-free
deb-src http://ftp.sjtu.edu.cn/debian/ squeeze main non-free contrib
deb-src http://ftp.sjtu.edu.cn/debian/ squeeze-proposed-updates main contrib non-free
deb-src http://ftp.sjtu.edu.cn/debian-security/ squeeze/updates main contrib non-free

保存修改
# ctrl + o 回�R
退�?/span>
# ctrl + x

更新�?/span>
# apt-get update

更新�pȝ��
# apt-get upgrade

安装SVN服务�?/strong>
# apt-get install subversion subversion-tools

安装完成后可以运行命令查看SVN服务器版本信�?/span>
# svnserve --version

配置SVN
首先创徏版本库的根目录，如位�|�：/home/svn/repository�Q�所有项目都��在该目录下创徏相应子文件夹
# mkdir –p /home/svn/repository

创徏��目版本库test�Q�仅为演�C�）
# svnadmin create /home/svn/repository/test

修改SVN配置文�g
nano /home/svn/repository/test/conf/svnserve.conf
以下为文件内容：
### This file controls the configuration of the svnserve daemon, if you
### use it to allow access to this repository. (If you only allow
### access through http: and/or file: URLs, then this file is
### irrelevant.)
### Visit http://subversion.tigris.org/ for more information.
[general]
### These options control access to the repository for unauthenticated
### and authenticated users. Valid values are "write", "read",
### and "none". The sample settings below are the defaults
# 未授权配�|��ؓ��止讉K��none�Q�已授权配置为可以读写write
anon-access = none
auth-access = write
### The password-db option controls the location of the password
### database file. Unless you specify a path starting with a /,
### the file's location is relative to the directory containing
### this configuration file.
### If SASL is enabled (see below), this file will NOT be used.
### Uncomment the line below to use the default password file.
# 用户数据库文�Ӟ��配置授权用户�Q�当前��用的文�g是和svnserve.conf在相同目录下的passwd文�g�Q�也可以指定其他�l�对路径文�g�Q�如�Q?home/svn/passwd
password-db = passwd
### The authz-db option controls the location of the authorization
### rules for path-based access control. Unless you specify a path
### starting with a /, the file's location is relative to the the
### directory containing this file. If you don't specify an
### authz-db, no path-based access control is done.
### Uncomment the line below to use the default authorization file.
# 授权文�g�Q�配�|�如同用户配�|?/span>
authz-db = authz
### This option specifies the authentication realm of the repository.
### If two repositories have the same authentication realm, they should
### have the same password database, and vice versa. The default realm
### is repository's uuid.
# realm = My First Repository
[sasl]
### This option specifies whether you want to use the Cyrus SASL
### library for authentication. Default is false.
### This section will be ignored if svnserve is not built with Cyrus
### SASL support; to check, run 'svnserve --version' and look for a line
### reading 'Cyrus SASL authentication is available.'
# use-sasl = true
### These options specify the desired strength of the security layer
### that you want SASL to provide. 0 means no encryption, 1 means
### integrity-checking only, values larger than 1 are correlated
### to the effective key length for encryption (e.g. 128 means 128-bit
### encryption). The values below are the defaults.
# min-encryption = 0
# max-encryption = 256

保存
# ctrl + o 回�R
退�?/span>
# ctrl + x
配置用户
# nano passwd
以下为文件内容：
### This file is an example password file for svnserve.
### Its format is similar to that of svnserve.conf. As shown in the
### example below it contains one section labelled [users].
### The name and password for each user follow, one account per line.
[users]
# harry = harryssecret
# sally = sallyssecret
IceWee = IceWee
增加用户IceWee�Q�密码也为IceWee�Q?号两侧需要有�I�格�Q�保�?ctrl + o 回�R)退�?ctrl + x)
配置讉K��权限
# nano authz
以下为文件内容：
### This file is an example authorization file for svnserve.
### Its format is identical to that of mod_authz_svn authorization
### files.
### As shown below each section defines authorizations for the path and
### (optional) repository specified by the section name.
### The authorizations follow. An authorization line can refer to:
### - a single user,
### - a group of users defined in a special [groups] section,
### - an alias defined in a special [aliases] section,
### - all authenticated users, using the '$authenticated' token,
### - only anonymous users, using the '$anonymous' token,
### - anyone, using the '*' wildcard.
###
### A match can be inverted by prefixing the rule with '~'. Rules can
### grant read ('r') access, read-write ('rw') access, or no access
### ('').
[aliases]
# joe = /C=XZ/ST=Dessert/L=Snake City/O=Snake Oil, Ltd./OU=Research Institute/CN=Joe Average
[groups]
# harry_and_sally = harry,sally
# harry_sally_and_joe = harry,sally,&joe
developers = IceWee
# [/foo/bar]
# harry = rw
# &joe = r
# * =
# [repository:/baz/fuz]
# @harry_and_sally = rw
# * = r
[/]
* = r
IceWee = rw
@developers = rw
[/tags]
IceWee = rw
默认所有用户可��d��根，IceWee可以��d��栏V��可以分别对子目录进行授权，如上的tags目录�Q�IceWee��h��d��权限�Q�以及IceWee所在的�l�developers也具备读写权限�?/span>

启动SVN服务�?/span>
# svnserve -d -r /home/svn/repository
-d含义为后台运行（daemon�Q�，-r指定的根目录�Q�如讉K��test应该使用�q�样的地址 svn://hostname:port/test

停止SVN服务
# killall svnserve

备䆾�q�原命��o�Q�与oracle的备份有些类�?/span>
导出
# svnadmin dump /home/svn/repository/test > /home/bak/test.dump

导入
# svnadmin load /home/svn/repository/demo < /home/bak/demo.dump
导入前提�Q?/span>
必须先创��导入版本库目录，如上的demo�Q�则需要做以下操作
# svnadmin create /home/svn/respository/demo
修改svnserve.conf、passwd、authz�{�文�Ӟ��前面已介�l?/span>

IceWee 2014-01-17 15:48 发表评论

IceWee — Thu, 21 Nov 2013 04:49:00 GMT

2013�q?2�?0�?br />---------------------------
冒��排序
void bubble(int[] array) {
        boolean swaped = true;
        for (int t = 1; t < array.length && swaped; t++) {
            swaped = false;
            for (int i = 0; i < array.length - t; i++) {
                if (array[i] > array[i + 1]) {
                   int temp = array[i];
                    array[i] = array[i + 1];
                    array[i + 1] = temp;
                    swaped = true;
                }
            }
        }
    }

2013�q?1�?6�?br />---------------------------
1、String的split�Ҏ��
�q�_��L��q�样用，String str = "a,b,c,d,e"; String[] arr = str.split(",");
其实�q�可以这��L��Q�String lan = "Java;C#?C++:C"; String si = lan.split("[;?:]"); �q�回的是字符串数�l�{"Java", "C#", "C++", "C"}

2013�q?1�?1�?br />---------------------------

1、Java对象池知多少�Q?br />�C�Z��Q�String s1 = "abc"; String s2 = "abc"; s1 == s2 �q�回ture�q�是false�Q�只要不是new出来的都先从对象池中��d��Q�因此结果�ؓtrue�Q�两个变量指向的是同一块内存空间地址�?br />
Java除了String�c�M��用了对象池以外，�q�有5个基本类型的��装�c�：Byte、Short、Integer、Long和Character�Q�例如：Integer inA = 20; Integer inB = 20; 那么 inA == inB 的结果�ؓtrue�Q�其他类与此相同�Q�不做示例�?br />
特别注意�Q?/strong>
(1)��点型的两个��装�c�Float和Double�q�没有参与对象池�Q?br />(2)整�Ş��装�c?Byte、Short、Integer和Long)只有数值小于或�{�于127时才使用对象池，例如�Q�Integer x = 128; Integer y = 128; x == y的结果�ؓfalse�?br />
2、Java变量命名规范
A. String #name = "Joe";
B. int $age = 30;
C. Double _height = 174.4;
D. float ~temp = 37.6;
以上A到D�Q�哪个无法通过�~�译�Q�答案是A和D�Q�因为Java变量名只允许字母、下划线(_)、美元符($)开��_��那么 int _ = 30; String $$ = "I DO";可以吗？�{�案是完全可以，但很��有��样定义变量名�Q�虽然没有违法命名规范，但最后我估计�E�序员自己都会被自己�l�晕�?br />
3�?�?能标识布��值吗�Q?br />int flag = 0;
if (flag) {
    System.out.print("error");
}
error会打印吗�Q�不会，因�ؓ�Ҏ��׃��会编译通过�Q�编译器会提�C�flag是int�c�d��而不是boolean�c�d��Q�如果你会有�q�种��x��可能之前学过C�Q�C�ȝ��0�?可以标识布尔的�?br />
4、静态导�?br />例：
ClassA.java
package bing.test.sub1;

public class ClassA {
  public static final int MAX_INT = Integer.MAX_VALUE;
}

ClassB.java
package bing.test.sub2;

import static bing.test.sub1.ClassA.MAX_INT;

public class ClassB {
public static void main(String[] args) {
System.out.println(MAX_INT);
}
}

输出�Q?147483647。不仅仅可以静态导入其他类的静态属性还可以导入静态方法，�q�些�Ҏ��在实际开发中很少见�?br />

IceWee 2013-11-21 12:49 发表评论

IceWee — Fri, 13 Sep 2013 08:32:00 GMT
Apache Commons的FTPClient局域网上传文�g速度本应该很快的�Q�但却在实际开发中发现上传一个文件蜗牛速度�Q�都是因��用了如下API�Q?br />
ftpClient.storeFile(fileName, inputStream)

原因是因为默认缓冲区大小�?024�Q�也��是1K�Q�当然慢了，在调用上传API之前重新修改以下默认讄��卛_��Q�如��缓冲区改�ؓ10M�Q�API�Q?br />
ftpClient.setBufferSize(1024 * 1024 * 10)

IceWee 2013-09-13 16:32 发表评论

Oracle查询锁表以及杀会话或系�l�进�E�来解除锁表操作

IceWee — Fri, 23 Aug 2013 02:20:00 GMT
�W�一步，查询锁表信息
--查询被锁住的数据库对�?/span>
select object_name, machine, s.sid, s.serial#
from v$locked_object l, dba_objects o, v$session s
where l.object_id = o.object_id
   and l.session_id = s.sid;

�W�二步，杀��L��据库会话
--杀��L��据库会话
alter system kill session '207,707'; -- 207为SID, 707为SERIAL#

�W�三步，如果�W�二步无法杀��M��话，报ORA-00031�Q�那么只能杀死UNIX/LINUX�pȝ��q�程�?br />
--查询当前操作的系�l�进�E�ID
select spid, osuser, s.program
from v$session s, v$process p
where s.paddr = p.addr
   and s.sid = 207; -- 207为SID

�W�四步，�Ҏ��查询到的�pȝ��PID�Q�杀掉进�E?br />
kill -9 24664 // 24664为UNIX/LINUX�pȝ��q�程ID

IceWee 2013-08-23 10:20 发表评论

HttpClientUtils

IceWee — Sat, 27 Jul 2013 03:53:00 GMT
     摘要: 备用。Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;...  阅读全文

IceWee 2013-07-27 11:53 发表评论

456亚洲精品成人影院,理论片在线观看理伦片,极品少妇一区二区三区

tomcat安装为服务service.bat讄����Q�启动服务时出错�Q�提�C��?..特定代码0�?

ORA-01438: value larger than specified precision allowed for this column & Could not synchronize database state with session

Debian �|�络讄���以及非法��x��后无法联�|?connect: network is unreachable

SVN(Subversion)自动同步备䆾配置

Oracle查询锁表以及杀会话或系�l�进�E�来解除锁表操作

HttpClientUtils

tomcat安装为服务service.bat讄��Q�启动服务时出错�Q�提�C��?..特定代码0�?

Debian �|�络讄��以及非法��x��后无法联�|?connect: network is unreachable